JPH0210790B2 - - Google Patents
Info
- Publication number
- JPH0210790B2 JPH0210790B2 JP58092514A JP9251483A JPH0210790B2 JP H0210790 B2 JPH0210790 B2 JP H0210790B2 JP 58092514 A JP58092514 A JP 58092514A JP 9251483 A JP9251483 A JP 9251483A JP H0210790 B2 JPH0210790 B2 JP H0210790B2
- Authority
- JP
- Japan
- Prior art keywords
- parts
- oxide ceramic
- weight
- ceramic powder
- thermoplastic resin
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000000843 powder Substances 0.000 claims description 81
- 229910052575 non-oxide ceramic Inorganic materials 0.000 claims description 67
- 239000011225 non-oxide ceramic Substances 0.000 claims description 67
- 229920005992 thermoplastic resin Polymers 0.000 claims description 45
- 238000005245 sintering Methods 0.000 claims description 36
- 238000001746 injection moulding Methods 0.000 claims description 34
- 239000002612 dispersion medium Substances 0.000 claims description 26
- 238000004519 manufacturing process Methods 0.000 claims description 23
- 239000000314 lubricant Substances 0.000 claims description 21
- 239000008240 homogeneous mixture Substances 0.000 claims description 20
- 239000004014 plasticizer Substances 0.000 claims description 18
- -1 acrylic ester Chemical class 0.000 claims description 16
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 claims description 15
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical group [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims description 15
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 claims description 13
- CERQOIWHTDAKMF-UHFFFAOYSA-N Methacrylic acid Chemical compound CC(=C)C(O)=O CERQOIWHTDAKMF-UHFFFAOYSA-N 0.000 claims description 12
- 238000000354 decomposition reaction Methods 0.000 claims description 11
- 238000002156 mixing Methods 0.000 claims description 11
- 239000002245 particle Substances 0.000 claims description 10
- 239000006185 dispersion Substances 0.000 claims description 9
- 238000002844 melting Methods 0.000 claims description 9
- 230000008018 melting Effects 0.000 claims description 9
- 239000000463 material Substances 0.000 claims description 8
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 claims description 7
- 229910052581 Si3N4 Inorganic materials 0.000 claims description 7
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 claims description 7
- 229910052580 B4C Inorganic materials 0.000 claims description 6
- INAHAJYZKVIDIZ-UHFFFAOYSA-N boron carbide Chemical compound B12B3B4C32B41 INAHAJYZKVIDIZ-UHFFFAOYSA-N 0.000 claims description 6
- 238000010438 heat treatment Methods 0.000 claims description 6
- PMHQVHHXPFUNSP-UHFFFAOYSA-M copper(1+);methylsulfanylmethane;bromide Chemical compound Br[Cu].CSC PMHQVHHXPFUNSP-UHFFFAOYSA-M 0.000 claims description 3
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 3
- 229910052582 BN Inorganic materials 0.000 claims description 2
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 claims description 2
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 claims description 2
- NRTOMJZYCJJWKI-UHFFFAOYSA-N Titanium nitride Chemical compound [Ti]#N NRTOMJZYCJJWKI-UHFFFAOYSA-N 0.000 claims description 2
- 229910026551 ZrC Inorganic materials 0.000 claims description 2
- OTCHGXYCWNXDOA-UHFFFAOYSA-N [C].[Zr] Chemical compound [C].[Zr] OTCHGXYCWNXDOA-UHFFFAOYSA-N 0.000 claims description 2
- CAVCGVPGBKGDTG-UHFFFAOYSA-N alumanylidynemethyl(alumanylidynemethylalumanylidenemethylidene)alumane Chemical compound [Al]#C[Al]=C=[Al]C#[Al] CAVCGVPGBKGDTG-UHFFFAOYSA-N 0.000 claims description 2
- 125000005397 methacrylic acid ester group Chemical group 0.000 claims description 2
- NFFIWVVINABMKP-UHFFFAOYSA-N methylidynetantalum Chemical compound [Ta]#C NFFIWVVINABMKP-UHFFFAOYSA-N 0.000 claims description 2
- 229910003468 tantalcarbide Inorganic materials 0.000 claims description 2
- MZLGASXMSKOWSE-UHFFFAOYSA-N tantalum nitride Chemical compound [Ta]#N MZLGASXMSKOWSE-UHFFFAOYSA-N 0.000 claims description 2
- MTPVUVINMAGMJL-UHFFFAOYSA-N trimethyl(1,1,2,2,2-pentafluoroethyl)silane Chemical compound C[Si](C)(C)C(F)(F)C(F)(F)F MTPVUVINMAGMJL-UHFFFAOYSA-N 0.000 claims description 2
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 claims description 2
- ZVWKZXLXHLZXLS-UHFFFAOYSA-N zirconium nitride Chemical compound [Zr]#N ZVWKZXLXHLZXLS-UHFFFAOYSA-N 0.000 claims description 2
- 238000010304 firing Methods 0.000 claims 1
- 238000000034 method Methods 0.000 description 37
- 239000000203 mixture Substances 0.000 description 29
- 238000005238 degreasing Methods 0.000 description 20
- 239000000919 ceramic Substances 0.000 description 16
- 229920001577 copolymer Polymers 0.000 description 11
- 238000000465 moulding Methods 0.000 description 10
- 239000000725 suspension Substances 0.000 description 10
- 239000004793 Polystyrene Substances 0.000 description 9
- 238000002347 injection Methods 0.000 description 9
- 239000007924 injection Substances 0.000 description 9
- 229920002223 polystyrene Polymers 0.000 description 9
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 8
- 229920005989 resin Polymers 0.000 description 8
- 239000011347 resin Substances 0.000 description 8
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 7
- 239000000654 additive Substances 0.000 description 7
- SOGAXMICEFXMKE-UHFFFAOYSA-N Butylmethacrylate Chemical compound CCCCOC(=O)C(C)=C SOGAXMICEFXMKE-UHFFFAOYSA-N 0.000 description 6
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 150000004767 nitrides Chemical class 0.000 description 6
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 6
- 230000000704 physical effect Effects 0.000 description 6
- 239000004743 Polypropylene Substances 0.000 description 5
- 235000021355 Stearic acid Nutrition 0.000 description 5
- 230000000996 additive effect Effects 0.000 description 5
- 238000005054 agglomeration Methods 0.000 description 5
- 230000002776 aggregation Effects 0.000 description 5
- 229910052799 carbon Inorganic materials 0.000 description 5
- 238000000280 densification Methods 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 5
- 229920000642 polymer Polymers 0.000 description 5
- 229920001155 polypropylene Polymers 0.000 description 5
- 239000008117 stearic acid Substances 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 4
- NIQCNGHVCWTJSM-UHFFFAOYSA-N Dimethyl phthalate Chemical compound COC(=O)C1=CC=CC=C1C(=O)OC NIQCNGHVCWTJSM-UHFFFAOYSA-N 0.000 description 4
- JIGUQPWFLRLWPJ-UHFFFAOYSA-N Ethyl acrylate Chemical compound CCOC(=O)C=C JIGUQPWFLRLWPJ-UHFFFAOYSA-N 0.000 description 4
- 229910052786 argon Inorganic materials 0.000 description 4
- 229910052796 boron Inorganic materials 0.000 description 4
- CQEYYJKEWSMYFG-UHFFFAOYSA-N butyl acrylate Chemical compound CCCCOC(=O)C=C CQEYYJKEWSMYFG-UHFFFAOYSA-N 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 239000013078 crystal Substances 0.000 description 4
- 230000007547 defect Effects 0.000 description 4
- 235000014113 dietary fatty acids Nutrition 0.000 description 4
- FLKPEMZONWLCSK-UHFFFAOYSA-N diethyl phthalate Chemical compound CCOC(=O)C1=CC=CC=C1C(=O)OCC FLKPEMZONWLCSK-UHFFFAOYSA-N 0.000 description 4
- 239000000194 fatty acid Substances 0.000 description 4
- 229930195729 fatty acid Natural products 0.000 description 4
- PNJWIWWMYCMZRO-UHFFFAOYSA-N pent‐4‐en‐2‐one Natural products CC(=O)CC=C PNJWIWWMYCMZRO-UHFFFAOYSA-N 0.000 description 4
- RUMACXVDVNRZJZ-UHFFFAOYSA-N 2-methylpropyl 2-methylprop-2-enoate Chemical compound CC(C)COC(=O)C(C)=C RUMACXVDVNRZJZ-UHFFFAOYSA-N 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- 239000004698 Polyethylene Substances 0.000 description 3
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 230000007797 corrosion Effects 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 3
- 239000005038 ethylene vinyl acetate Substances 0.000 description 3
- 238000009472 formulation Methods 0.000 description 3
- 230000009477 glass transition Effects 0.000 description 3
- 239000011368 organic material Substances 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- SIWVEOZUMHYXCS-UHFFFAOYSA-N oxo(oxoyttriooxy)yttrium Chemical compound O=[Y]O[Y]=O SIWVEOZUMHYXCS-UHFFFAOYSA-N 0.000 description 3
- 229920001200 poly(ethylene-vinyl acetate) Polymers 0.000 description 3
- 229920000573 polyethylene Polymers 0.000 description 3
- 238000001272 pressureless sintering Methods 0.000 description 3
- 239000000377 silicon dioxide Substances 0.000 description 3
- 239000001993 wax Substances 0.000 description 3
- GOXQRTZXKQZDDN-UHFFFAOYSA-N 2-Ethylhexyl acrylate Chemical compound CCCCC(CC)COC(=O)C=C GOXQRTZXKQZDDN-UHFFFAOYSA-N 0.000 description 2
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- 239000004925 Acrylic resin Substances 0.000 description 2
- BAPJBEWLBFYGME-UHFFFAOYSA-N Methyl acrylate Chemical compound COC(=O)C=C BAPJBEWLBFYGME-UHFFFAOYSA-N 0.000 description 2
- 240000000136 Scabiosa atropurpurea Species 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 description 2
- 125000000484 butyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 2
- FBSAITBEAPNWJG-UHFFFAOYSA-N dimethyl phthalate Natural products CC(=O)OC1=CC=CC=C1OC(C)=O FBSAITBEAPNWJG-UHFFFAOYSA-N 0.000 description 2
- 229960001826 dimethylphthalate Drugs 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 239000008187 granular material Substances 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 238000004898 kneading Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 2
- 239000000088 plastic resin Substances 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- LYBIZMNPXTXVMV-UHFFFAOYSA-N propan-2-yl prop-2-enoate Chemical compound CC(C)OC(=O)C=C LYBIZMNPXTXVMV-UHFFFAOYSA-N 0.000 description 2
- PNXMTCDJUBJHQJ-UHFFFAOYSA-N propyl prop-2-enoate Chemical compound CCCOC(=O)C=C PNXMTCDJUBJHQJ-UHFFFAOYSA-N 0.000 description 2
- 239000011863 silicon-based powder Substances 0.000 description 2
- 238000001721 transfer moulding Methods 0.000 description 2
- JHPBZFOKBAGZBL-UHFFFAOYSA-N (3-hydroxy-2,2,4-trimethylpentyl) 2-methylprop-2-enoate Chemical compound CC(C)C(O)C(C)(C)COC(=O)C(C)=C JHPBZFOKBAGZBL-UHFFFAOYSA-N 0.000 description 1
- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical compound [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 description 1
- YXYJVFYWCLAXHO-UHFFFAOYSA-N 2-methoxyethyl 2-methylprop-2-enoate Chemical compound COCCOC(=O)C(C)=C YXYJVFYWCLAXHO-UHFFFAOYSA-N 0.000 description 1
- CFVWNXQPGQOHRJ-UHFFFAOYSA-N 2-methylpropyl prop-2-enoate Chemical compound CC(C)COC(=O)C=C CFVWNXQPGQOHRJ-UHFFFAOYSA-N 0.000 description 1
- YLZOPXRUQYQQID-UHFFFAOYSA-N 3-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)-1-[4-[2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidin-5-yl]piperazin-1-yl]propan-1-one Chemical compound N1N=NC=2CN(CCC=21)CCC(=O)N1CCN(CC1)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F YLZOPXRUQYQQID-UHFFFAOYSA-N 0.000 description 1
- ULYIFEQRRINMJQ-UHFFFAOYSA-N 3-methylbutyl 2-methylprop-2-enoate Chemical compound CC(C)CCOC(=O)C(C)=C ULYIFEQRRINMJQ-UHFFFAOYSA-N 0.000 description 1
- ZVYGIPWYVVJFRW-UHFFFAOYSA-N 3-methylbutyl prop-2-enoate Chemical compound CC(C)CCOC(=O)C=C ZVYGIPWYVVJFRW-UHFFFAOYSA-N 0.000 description 1
- FHVDTGUDJYJELY-UHFFFAOYSA-N 6-{[2-carboxy-4,5-dihydroxy-6-(phosphanyloxy)oxan-3-yl]oxy}-4,5-dihydroxy-3-phosphanyloxane-2-carboxylic acid Chemical compound O1C(C(O)=O)C(P)C(O)C(O)C1OC1C(C(O)=O)OC(OP)C(O)C1O FHVDTGUDJYJELY-UHFFFAOYSA-N 0.000 description 1
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- 208000015943 Coeliac disease Diseases 0.000 description 1
- 229920002261 Corn starch Polymers 0.000 description 1
- UDSFAEKRVUSQDD-UHFFFAOYSA-N Dimethyl adipate Chemical compound COC(=O)CCCCC(=O)OC UDSFAEKRVUSQDD-UHFFFAOYSA-N 0.000 description 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- ZZSNKZQZMQGXPY-UHFFFAOYSA-N Ethyl cellulose Chemical compound CCOCC1OC(OC)C(OCC)C(OCC)C1OC1C(O)C(O)C(OC)C(CO)O1 ZZSNKZQZMQGXPY-UHFFFAOYSA-N 0.000 description 1
- 239000001856 Ethyl cellulose Substances 0.000 description 1
- 239000005977 Ethylene Substances 0.000 description 1
- WOBHKFSMXKNTIM-UHFFFAOYSA-N Hydroxyethyl methacrylate Chemical compound CC(=C)C(=O)OCCO WOBHKFSMXKNTIM-UHFFFAOYSA-N 0.000 description 1
- 229920002153 Hydroxypropyl cellulose Polymers 0.000 description 1
- 229920001732 Lignosulfonate Polymers 0.000 description 1
- VVQNEPGJFQJSBK-UHFFFAOYSA-N Methyl methacrylate Chemical compound COC(=O)C(C)=C VVQNEPGJFQJSBK-UHFFFAOYSA-N 0.000 description 1
- 239000004677 Nylon Substances 0.000 description 1
- 229920003171 Poly (ethylene oxide) Polymers 0.000 description 1
- 239000002202 Polyethylene glycol Substances 0.000 description 1
- 229920000265 Polyparaphenylene Polymers 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- 241000872198 Serjania polyphylla Species 0.000 description 1
- 239000006061 abrasive grain Substances 0.000 description 1
- 239000006230 acetylene black Substances 0.000 description 1
- 125000005396 acrylic acid ester group Chemical group 0.000 description 1
- 229920006243 acrylic copolymer Polymers 0.000 description 1
- XECAHXYUAAWDEL-UHFFFAOYSA-N acrylonitrile butadiene styrene Chemical compound C=CC=C.C=CC#N.C=CC1=CC=CC=C1 XECAHXYUAAWDEL-UHFFFAOYSA-N 0.000 description 1
- 239000004676 acrylonitrile butadiene styrene Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- WNLRTRBMVRJNCN-UHFFFAOYSA-N adipic acid Chemical class OC(=O)CCCCC(O)=O WNLRTRBMVRJNCN-UHFFFAOYSA-N 0.000 description 1
- 229940072056 alginate Drugs 0.000 description 1
- 229920000615 alginic acid Polymers 0.000 description 1
- 235000010443 alginic acid Nutrition 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 229910052790 beryllium Inorganic materials 0.000 description 1
- ATBAMAFKBVZNFJ-UHFFFAOYSA-N beryllium atom Chemical compound [Be] ATBAMAFKBVZNFJ-UHFFFAOYSA-N 0.000 description 1
- RNOOHTVUSNIPCJ-UHFFFAOYSA-N butan-2-yl prop-2-enoate Chemical group CCC(C)OC(=O)C=C RNOOHTVUSNIPCJ-UHFFFAOYSA-N 0.000 description 1
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 1
- 239000000292 calcium oxide Substances 0.000 description 1
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 1
- 150000001720 carbohydrates Chemical class 0.000 description 1
- 239000006229 carbon black Substances 0.000 description 1
- 229920002301 cellulose acetate Polymers 0.000 description 1
- 229920006217 cellulose acetate butyrate Polymers 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- FCSHDIVRCWTZOX-DVTGEIKXSA-N clobetasol Chemical compound C1CC2=CC(=O)C=C[C@]2(C)[C@]2(F)[C@@H]1[C@@H]1C[C@H](C)[C@@](C(=O)CCl)(O)[C@@]1(C)C[C@@H]2O FCSHDIVRCWTZOX-DVTGEIKXSA-N 0.000 description 1
- 239000011294 coal tar pitch Substances 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000008120 corn starch Substances 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- OIWOHHBRDFKZNC-UHFFFAOYSA-N cyclohexyl 2-methylprop-2-enoate Chemical compound CC(=C)C(=O)OC1CCCCC1 OIWOHHBRDFKZNC-UHFFFAOYSA-N 0.000 description 1
- KBLWLMPSVYBVDK-UHFFFAOYSA-N cyclohexyl prop-2-enoate Chemical compound C=CC(=O)OC1CCCCC1 KBLWLMPSVYBVDK-UHFFFAOYSA-N 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- FWLDHHJLVGRRHD-UHFFFAOYSA-N decyl prop-2-enoate Chemical compound CCCCCCCCCCOC(=O)C=C FWLDHHJLVGRRHD-UHFFFAOYSA-N 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 229910003460 diamond Inorganic materials 0.000 description 1
- 239000010432 diamond Substances 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- GMSCBRSQMRDRCD-UHFFFAOYSA-N dodecyl 2-methylprop-2-enoate Chemical compound CCCCCCCCCCCCOC(=O)C(C)=C GMSCBRSQMRDRCD-UHFFFAOYSA-N 0.000 description 1
- 239000011363 dried mixture Substances 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- SUPCQIBBMFXVTL-UHFFFAOYSA-N ethyl 2-methylprop-2-enoate Chemical compound CCOC(=O)C(C)=C SUPCQIBBMFXVTL-UHFFFAOYSA-N 0.000 description 1
- FKIRSCKRJJUCNI-UHFFFAOYSA-N ethyl 7-bromo-1h-indole-2-carboxylate Chemical compound C1=CC(Br)=C2NC(C(=O)OCC)=CC2=C1 FKIRSCKRJJUCNI-UHFFFAOYSA-N 0.000 description 1
- 229920001249 ethyl cellulose Polymers 0.000 description 1
- 235000019325 ethyl cellulose Nutrition 0.000 description 1
- STVZJERGLQHEKB-UHFFFAOYSA-N ethylene glycol dimethacrylate Chemical compound CC(=C)C(=O)OCCOC(=O)C(C)=C STVZJERGLQHEKB-UHFFFAOYSA-N 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 150000004665 fatty acids Chemical class 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 238000007730 finishing process Methods 0.000 description 1
- 238000004108 freeze drying Methods 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- DWXAVNJYFLGAEF-UHFFFAOYSA-N furan-2-ylmethyl 2-methylprop-2-enoate Chemical compound CC(=C)C(=O)OCC1=CC=CO1 DWXAVNJYFLGAEF-UHFFFAOYSA-N 0.000 description 1
- 125000003055 glycidyl group Chemical group C(C1CO1)* 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- LNCPIMCVTKXXOY-UHFFFAOYSA-N hexyl 2-methylprop-2-enoate Chemical compound CCCCCCOC(=O)C(C)=C LNCPIMCVTKXXOY-UHFFFAOYSA-N 0.000 description 1
- LNMQRPPRQDGUDR-UHFFFAOYSA-N hexyl prop-2-enoate Chemical compound CCCCCCOC(=O)C=C LNMQRPPRQDGUDR-UHFFFAOYSA-N 0.000 description 1
- 239000007970 homogeneous dispersion Substances 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 239000001863 hydroxypropyl cellulose Substances 0.000 description 1
- 235000010977 hydroxypropyl cellulose Nutrition 0.000 description 1
- PBOSTUDLECTMNL-UHFFFAOYSA-N lauryl acrylate Chemical compound CCCCCCCCCCCCOC(=O)C=C PBOSTUDLECTMNL-UHFFFAOYSA-N 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 239000000395 magnesium oxide Substances 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 125000005395 methacrylic acid group Chemical group 0.000 description 1
- 239000002480 mineral oil Substances 0.000 description 1
- 239000012778 molding material Substances 0.000 description 1
- 125000000740 n-pentyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
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Description
本発明は、非酸化物セラミツクス焼結体の製造
方法に関し、特に本発明は、極めて複雑な形状を
有する生成形体を容易にかつ高精度に製造するこ
とのできる射出成形法を用いる非酸化物セラミツ
クス焼結体の製造方法に関する。
最近、電子工業、原子力工業、高温工業などの
各種の分野における工業技術の発展に伴つて材料
に要求される性能は益々苛酷になつている。その
ためセラミツクスの分野においても従来知られた
酸化物以外の機械的、熱的、電気的、化学的性質
等に優れた非酸化物セラミツクスへの関心が高ま
つている。
前記非酸化物セラミツクスに期待される主な用
途はガスタービン部品、高温熱交換器のような苛
酷な条件下で使用される高温構造材あるいはケミ
カルポンプ部品、エンジン部品、メカニカルシー
ル等の著しい腐食や摩耗を受ける条件下で使用さ
れる耐食耐摩耗性材料等が挙げられるが、いずれ
も複雑な形状でかつ寸法精度に優れたものが要求
されている。
前述の如き複雑な形状でかつ寸法精度に優れた
非酸化物セラミツクスの製造方法としては、あら
かじめ成形した生成形体を焼結する方法、すなわ
ち常圧焼結法あるいは反応焼結法が有利である。
前記生成形体を成形する手段としては、射出成形
法、トランスフアー成形法、スリツプキヤステイ
ング法、乾式または湿式加圧プレス法、ラバープ
レス法および押し出し成形法等が一般に知られて
いる。
このうち、射出成形法は極めて複雑で、寸法精
度の優れた生成形体を大量にかつ迅速に繰返し製
造することができ、しかも仕上げ工程としての機
械加工を殆ど必要としない極めて有利な方法であ
り、従来、前記射出成形法によるセラミツクス焼
結体の製造方法が種々報告されている。
例えば、特公昭51−29170号公報に、窯業原料
100部に対して有機添加剤として熱可塑性樹脂で
あるアタツクチツクポリプロピレン５〜20部と滑
剤および可塑剤をそれぞれ５部以下添加して射出
成形用材料とする射出成形用組成物が開示されて
いる。
しかしながら、前記発明で使用されるアタツク
チツクポリプロピレンは揮発分解温度が比較的高
く、脱脂処理を行なう際に、酸化性雰囲気を適用
することが不適当な非酸化物セラミツクスに適用
する場合には比較的高温で脱脂処理しなければな
らず、しかも脱脂に要する時間が著しく長くなる
欠点を有している。
また、米国特許第4233256号公報に炭化物セラ
ミツクス粉末を射出成形法によつて成形し、焼結
体を製造する方法が開示されている。前記公報記
載の方法は熱可塑性樹脂としてスチレン、ポリス
チレン、スチレン誘導体を使用する方法であり、
また成形時における射出圧力の好適範囲は約4500
〜9000psi（約697.5〜1395Kg／cm2）と比較的高い
圧力を必要とする方法である。
しかしながら、上述の如き高い圧力でもつて生
成形体を成形すると、射出成形機や金型の摩耗が
著しく、寿命が短かくなるばかりでなく、焼結体
に不純物が混入する等の欠点がある。
ところで、本発明において使用することのでき
る非酸化物セラミツクス粉末は一般に難焼結性の
ものが多く、焼結用の粉末は焼結特性を向上させ
ることを目的として、従来より使用されているセ
ラミツクス粉末に比較して微細で比表面積の大き
なものが要求され使用される。しかしながら、射
出成形法において前述の如き微細で比表面積の大
きなセラミツクス粉末を使用する場合、通常の射
出成形の際に使用される程度の熱可塑性樹脂添加
量でもつて微細な非酸化物セラミツクス粉末の表
面を十分に被覆することは困難であり、一部樹脂
によつて被覆されていない粉末を生ずるため射出
成形時の流動性を向上させる効果が小さく、前述
の如き射出成形法によつて微細な非酸化物セラミ
ツクス粉末を生成形体に成形するためには比較的
高い成形圧力を必要とし、射出成形機や金型の摩
耗が著しく寿命が短いばかりでなく焼結体中に不
純物が混入し易い等の欠点があつた。
前述の如き欠点を除去する方法としては熱可塑
性樹脂、潤滑剤あるいは可塑剤等の有機質材料の
添加量を増加することによつてセラミツクス組成
物の成形性を向上させる方法が一般的に考えられ
るが、このように有機質材料の添加量を増加する
と前記有機質材料に要する費用が増大するばかり
でなく、脱脂処理に要する時間が著しく長くな
り、さらに脱脂処理後の生成形体密度が低くなる
ため高密度の焼結体を得ることが困難となり実用
的ではない。
上述の如き観点に基き、本発明者らは射出成形
に適した非酸化物セラミツクス組成物を得るため
の研究を種々行なつた結果、前記非酸化物セラミ
ツクス粉末に対する被覆性が極めて良好で比較的
少量の配合量でもつて従来想像だにされなかつた
程の極めて良好な成形性を与えることのできる驚
くべき効果を発揮する熱可塑性樹脂を新規に知見
し、さらに前記熱可塑性樹脂を使用することによ
つて従来得ることの困難であつた極めて高密度の
焼結体を容易に得ることのできることを知見する
に至り、先に特開昭58−99171号により、「主とし
て非酸化物セラミツクス粉末と必要により添加さ
れる焼結助剤と熱可塑性樹脂と潤滑剤と必要によ
り添加される可塑剤とからなる組成物において、
前記潤滑剤と可塑剤は通常射出成形において使用
されるものであり、熱可塑性樹脂は主としてアク
リル酸、メタクリル酸、およびそれらの誘導体の
なかから選ばれる少なくとも１種の重合体である
ことを特徴とする射出成形に適したセラミツクス
組成物」およびその組成物を使用してなる非酸化
物セラミツクス焼結体の製造方法に係る発明を提
案している。
前記発明によれば、前記熱可塑性樹脂を混合す
ることによつて得られる混合物は射出成形性に極
めて優れており、比較的低い成形圧力で容易に生
成形体を成形することができる。
前記発明において、前記熱可塑性樹脂を混合し
た混合物が射出成形性に極めて優れている理由
は、前記熱可塑性樹脂は非酸化物セラミツクス粉
末に対する被覆性が極めて良好で、射出成形時の
流動性を著しく向上させることができることによ
るものと考えられる。
ところで、本発明において使用される如き微細
で比表面積の大きな非酸化物セラミツクス粉末は
極めて凝集性が強いため凝集を充分にほぐして均
一に分散させた状態の混合物を得ることが困難で
一部凝集粒子のままの状態の非酸化物セラミツク
ス粉末を含有する場合があり、このような凝集粒
子のままの状態の非酸化物セラミツクス粉末を含
有する混合物を使用して生成形体を成形すると、
焼結時に前記非酸化物セラミツクス粉末の凝集に
起因するミクロ的な焼結体密度あるいは結晶粒径
等のバラツキを生じ焼結体の物性特に曲げ強度を
著しく劣化させる原因となつていることを知見し
た。したがつて、特に高強度で信頼性の高い焼結
体を得ようとする場合には前記混合物は非酸化物
セラミツクス粉末の凝集粒子を含有しないもので
あることが重要である。
本発明は前述の如き欠点を除去改善し、非酸化
物セラミツクス粉末が均一な分散状態にある射出
成形に適した非酸化物セラミツクス組成物よりな
る均一混合物を製造し、つぎにこの混合物を射出
成形し無加圧焼結することにより高強度で均質な
非酸化物セラミツクス焼結体の製造方法を提供す
ることを目的とするものである。
本発明によれば、主として非酸化物セラミツク
ス粉末と熱可塑性樹脂、潤滑剤、および焼結助剤
もしくは可塑剤のいずれか少なくとも１種とから
なる均一混合物を、射出成形によつて所望の形状
の生成形体に成形し、その後、この生成形体を加
熱して前記熱可塑性樹脂および潤滑剤ならびに可
塑剤を揮発分解させることによつて除去し脱脂生
成形体となし、ついでこの脱脂生成形体を焼成し
て非酸化物セラミツクス焼結体を製造する方法に
おいて、
前記均一混合物中に添加して各非酸化物セラミ
ツクス粉末を被覆する前記熱可塑性樹脂として、
アクリル酸、メタクリル酸のいずれか少なくとも
１種が１〜５重量部、アクリル酸エステルが30〜
85重量部およびメタクリル酸エステルが10〜69重
量部の割合で共重合したものを主成分とするもの
を用い、しかもその熱可塑性樹脂被覆非酸化物セ
ラミツクス粉末を主体とする前記均一混合物を、
分散媒液中で予め混合し均一分散処理を施し、そ
の後前記分散媒液の融点より低い温度まで急冷し
て凍結させ、ついで前記凍結させた凍結物中の分
散媒液を減圧下で昇華乾燥せしめることを特徴と
する非酸化物セラミツクス焼結体の製造方法によ
つて前記目的を達成することができる。
次に本発明を詳細に説明する。
前述の如く、射出成形用非酸化物セラミツクス
組成物中の非酸化物セラミツクス粉末は均一な分
散状態にあつてかつ熱可塑性樹脂によつてその表
面が均一に被覆されていることが重要であるが、
従来かかる本発明で使用される如き極めて微細な
非酸化物セラミツクス粉末を均一な分散状態とな
しかつその表面に熱可塑性樹脂を均一に被覆する
ための適切な方法は知られていなかつた。
本発明者らは非酸化物セラミツクス粉末を均一
な分散状態となしかつその表面に熱可塑性樹脂を
均一に被覆するための研究を種々行ない、非酸化
物セラミツクス粉末と熱可塑性樹脂を分散媒液中
に投入して混合し均一分散処理を施した後前記分
散媒液の融点より低い温度まで急冷して凍結さ
せ、ついで前記凍結させた凍結物中の分散媒液を
減圧下で昇華乾燥せしめる方法に想到して本発明
を完成した。
すなわち、本発明で使用される如き極めて微細
な非酸化物セラミツクス粉末は一般に凝集性の強
い粉末であり、従来行なわれている如き単に熱可
塑性樹脂を添加し加熱しながら混練するだけでは
非酸化物セラミツクス粉末の凝集をほぐして熱可
塑性樹脂を粉末の表面に均一に被覆せしめること
は極めて困難であるが、本発明者らは非酸化物セ
ラミツクス粉末と熱可塑性樹脂を分散媒液中に投
入して混合することにより極めて均一な混合状態
の懸濁液を得ることができ、さらに前記懸濁液を
分散媒液の融点より低い温度まで急冷して短時間
のうちに凍結させることにより、非酸化物セラミ
ツクスの凝集を防止することができ、ついで前記
凍結させた凍結物中の分散媒液を減圧下で昇華乾
燥せしめることにより、非酸化物セラミツクス粉
末の均一な分散状態を維持したままその表面に熱
可塑性樹脂を均一に被覆せしめることができる。
本発明によれば、前記均一混合物のうち少なく
とも非酸化物セラミツクス粉末と熱可塑性樹脂は
あらかじめ分散媒液中で混合し均一分散処理を施
した後、前記分散媒液の融点より低い温度まで急
冷して凍結させ、ついで前記凍結物中の分散媒液
を減圧下で昇華乾燥せしめたものであることが必
要であるが、前記必要により添加される焼結助剤
は非酸化物セラミツクス粉末と熱可塑性樹脂とを
分散媒液中で混合する前に非酸化物セラミツクス
粉末と混合しておくことが有利である。
本発明によれば、前記均一分散処理の施された
懸濁液はなるべく短時間のうちに凍結させること
が望ましく、前記懸濁液は分散媒液の融点より低
い温度に維持された雰囲気中へ噴霧して凍結させ
ることが有利である。
本発明によれば、前記均一分散処理は振動ミ
ル、アトライター、ボールミル、コロイドミルあ
るいは高速ミキサー等の強い剪断力を与えること
のできる分散装置を使用することが有利である。
本発明によれば、前述の如くして凍結乾燥され
た混合物は容器内を加熱することのできる混合機
中に投入され約150〜200℃の温度に加熱されなが
ら充分に混練された後冷却固化され、ついで破砕
整粒されて射出成形用の均一混合物が調整され
る。前記容器内を加熱することのできる混合機と
しては例えばラボプラストミル混合機を有利に使
用することができる。
なお、前記潤滑剤と可塑剤は前記分散媒液中に
添加して混合する方法あるいは分散媒液を乾燥除
去した後の加熱混練時に添加して混合する方法の
いずれの方法においても有利に混合することがで
きる。
本発明によれば、前記分散媒液は融点が−５〜
15℃の範囲内のものを使用することが有利であ
り、なかでもベンゼン、シクロヘキサンより選ば
れるいずれか少なくとも１種であることが好まし
い。
本発明によれば、前記分散媒液の配合量は非酸
化物セラミツクス粉末100重量部に対して少なく
とも200重量部であることが好ましい。その理由
は前記分散媒液の配合量が200重量部より少ない
と懸濁液の粘性が高く非酸化物セラミツクス粉末
を充分に分散することが困難であるため非酸化物
セラミツクス粉末の表面を熱可塑性樹脂で均一に
被覆することが困難であるからである。前記分散
媒液の配合量は均一な混合状態の懸濁液を得ると
いう目的を考慮すると分散媒液の配合量はなるべ
く多い方が有利であるが、あまり多いと凍結乾燥
に要する時間が長くまた単位設備当りの組成物製
造能力が減少するため経済的でなく、前記配合量
は300〜1000重量部の範囲内とすることが有利で
ある。
本発明によれば、前記熱可塑性樹脂としてエチ
ルセルロース、ABS、アクリル酸樹脂、ヒドロ
キシプロピルセルロース、ポリエチレン、ポリプ
ロピレン、酢酸セルロース、ナイロン、ポリビニ
ルブチラール、エチレン、アクリル共重合体、セ
ルロースアセテートブチレート、ポリスチレン、
ポリスルフオン、ポリエチレングリコール、ポリ
エチレンオキサイド等を使用することができる
が、なかでもアクリル酸、メタクリル酸およびそ
れらの誘導体のなかから選ばれる少なくとも１種
の重合体よりなるアクリル酸樹脂を主成分とする
ことが好ましい。
前記アクリル酸の誘導体としてはアクリル酸エ
ステルが好ましく、例えばアクリル酸メチル、ア
クリル酸エチル、アクリル酸−ｎ−プロピル、ア
クリル酸−iso−プロピル、アクリル酸−ｎ−ブ
チル、アクリル酸−iso−ブチル、アクリル酸−
sec−ブチル、アクリル酸−tert−ブチル、アク
リル酸−ｎ−アミル、アクリル酸−iso−アミル、
アクリル酸−sec−アミル、アクリル酸−tert−
アミル、アクリル酸ヘキシル、アクリル酸シクロ
ヘキシル、アクリル酸オクチル、アクリル酸ノニ
ル、アクリル酸デシル、アクリル酸ドデシル、ア
クリル酸フルフリル、アクリル酸グリシジル、ア
クリル酸２−エチルヘキシルを使用することが有
利であり、なかでもアクリル酸エチル、アクリル
酸−ｎ−プロピル、アクリル酸−iso−プロピル、
アクリル酸−ｎ−ブチル、アクリル酸２−エチル
ヘキシルが最適である。
前記メタクリル酸の誘導体としてはメタクリル
酸エステルが好ましく、例えばメタクリル酸メチ
ル、メタクリル酸エチル、メタクリル酸−ｎ−プ
ロピル、メタクリル酸−iso−プロピル、メタク
リル酸−ｎ−ブチル、メタクリル酸−iso−ブチ
ル、メタクリル酸−sec−ブチル、メタクリル酸
−tert−ブチル、メタクリル酸−ｎ−アミル、メ
タクリル酸−iso−アミル、メタクリル酸ヘキシ
ル、メタクリル酸シクロヘキシル、メタクリル酸
オクチル、メタクリル酸ドデシル、メタクリル酸
フルフリル、メタクリル酸グリシジル、メタクリ
ル酸２−ヒドロキシエチル、エチレングリコー
ル、ジメタクリレート、メタクリル酸βメトキシ
エチルを使用することが有利であり、なかでもメ
タクリル酸−ｎ−ブチル、メタクリル酸−iso−
ブチルが最適である。
本発明によれば、前記熱可塑性樹脂はアクリル
酸、メタクリル酸のいずれか少なくとも１種を１
〜５重量部、アクリル酸エステルを30〜85重量部
およびメタクリル酸エステルを10〜69重量部の割
合で共重合させたものを主成分とするものである
ことが最も好ましい。
なお、上記アクリル酸、メタクリル酸およびそ
れらの誘導体よりなる共重合体と従来広く使用さ
れている他の有機樹脂例えばポリスチレン、ポリ
プロピレン、ポリエチレン等とをガラス転移温度
ならびに分解温度について比較して下記の第１表
に示す。
The present invention relates to a method for producing a non-oxide ceramic sintered body, and in particular, the present invention relates to a method for producing a non-oxide ceramic sintered body using an injection molding method that enables the production of a sintered body having an extremely complicated shape with ease and high precision. The present invention relates to a method for manufacturing a sintered body. Recently, with the development of industrial technology in various fields such as electronic industry, nuclear industry, and high temperature industry, the performance required of materials has become increasingly severe. Therefore, in the field of ceramics, there is increasing interest in non-oxide ceramics that have superior mechanical, thermal, electrical, chemical properties, etc. other than conventionally known oxides. The main applications expected for the above-mentioned non-oxide ceramics are gas turbine parts, high-temperature structural materials used under harsh conditions such as high-temperature heat exchangers, and severe corrosion and corrosion of chemical pump parts, engine parts, mechanical seals, etc. Examples include corrosion-resistant and wear-resistant materials that are used under conditions of wear, but all of them are required to have complex shapes and excellent dimensional accuracy. As a method for producing non-oxide ceramics having a complex shape and excellent dimensional accuracy as described above, it is advantageous to use a method of sintering a preformed green body, that is, an atmospheric pressure sintering method or a reaction sintering method.
Injection molding, transfer molding, slip casting, dry or wet pressure pressing, rubber pressing, extrusion molding, and the like are generally known as means for molding the formed body. Among these, the injection molding method is extremely complex, and is an extremely advantageous method that allows for the rapid and repeated manufacture of formed bodies with excellent dimensional accuracy in large quantities, and also requires almost no machining as a finishing process. Conventionally, various methods for producing ceramic sintered bodies using the injection molding method have been reported. For example, in Japanese Patent Publication No. 51-29170, ceramic raw materials
Disclosed is an injection molding composition in which 5 to 20 parts of adhesive polypropylene, which is a thermoplastic resin, and 5 parts or less of each of a lubricant and a plasticizer are added as organic additives to 100 parts of the injection molding material. There is. However, the attacking polypropylene used in the above invention has a relatively high volatile decomposition temperature, and when applied to non-oxide ceramics for which it is inappropriate to apply an oxidizing atmosphere during degreasing, It has the disadvantage that it must be degreased at a high temperature, and the time required for degreasing is extremely long. Further, US Pat. No. 4,233,256 discloses a method of manufacturing a sintered body by molding carbide ceramic powder by an injection molding method. The method described in the above publication uses styrene, polystyrene, or styrene derivatives as the thermoplastic resin,
Also, the preferred range of injection pressure during molding is approximately 4500
This method requires a relatively high pressure of ~9000 psi (approximately 697.5 to 1395 Kg/cm 2 ). However, when the formed body is molded under the above-mentioned high pressure, there are disadvantages such as significant wear of the injection molding machine and the mold, shortening the life span, and contamination of the sintered body with impurities. Incidentally, many of the non-oxide ceramic powders that can be used in the present invention are generally difficult to sinter, and the sintering powder is made from conventionally used ceramic powders for the purpose of improving sintering properties. It is required to be used because it is finer and has a larger specific surface area than powder. However, when using fine ceramic powder with a large specific surface area as described above in the injection molding method, even if the amount of thermoplastic resin added is the same as that used in normal injection molding, the surface of the fine non-oxide ceramic powder It is difficult to sufficiently cover the resin, and as this results in powder that is partially uncovered by the resin, the effect of improving fluidity during injection molding is small. Comparatively high molding pressure is required to mold oxide ceramic powder into a green body, which not only significantly shortens the life of the injection molding machine and the mold, but also makes it easy for impurities to get mixed into the sintered body. There were flaws. As a method to eliminate the above-mentioned defects, it is generally considered to improve the moldability of ceramic compositions by increasing the amount of organic materials such as thermoplastic resins, lubricants, or plasticizers. Increasing the amount of organic material added not only increases the cost required for the organic material, but also significantly lengthens the time required for degreasing.Furthermore, the density of the formed bodies after degreasing decreases, resulting in a high-density product. It is difficult to obtain a sintered body and is not practical. Based on the above-mentioned viewpoints, the present inventors conducted various studies to obtain a non-oxide ceramic composition suitable for injection molding, and as a result, the coating properties for the non-oxide ceramic powder were extremely good and relatively We have discovered a new thermoplastic resin that exhibits the surprising effect of providing extremely good moldability that was previously unimaginable even with a small amount of compounding, and we have also discovered the use of this thermoplastic resin. As a result, it was discovered that extremely high-density sintered bodies, which had been difficult to obtain in the past, could be easily obtained. In a composition consisting of a sintering aid added by, a thermoplastic resin, a lubricant, and a plasticizer added as necessary,
The lubricant and plasticizer are those commonly used in injection molding, and the thermoplastic resin is mainly at least one polymer selected from acrylic acid, methacrylic acid, and derivatives thereof. The present invention proposes an invention relating to a ceramic composition suitable for injection molding and a method for manufacturing a non-oxide ceramic sintered body using the composition. According to the invention, the mixture obtained by mixing the thermoplastic resins has extremely excellent injection moldability, and can be easily molded into a product at a relatively low molding pressure. In the invention, the reason why the mixture containing the thermoplastic resin has extremely excellent injection moldability is that the thermoplastic resin has extremely good coating properties with respect to non-oxide ceramic powder, and significantly improves fluidity during injection molding. This is thought to be due to the fact that it can be improved. By the way, the fine non-oxide ceramic powder with a large specific surface area as used in the present invention has extremely strong agglomeration, so it is difficult to sufficiently break up the agglomerations and obtain a uniformly dispersed mixture. It may contain non-oxide ceramic powder in the form of particles, and when a formed body is molded using a mixture containing such non-oxide ceramic powder in the form of aggregated particles,
It was discovered that during sintering, agglomeration of the non-oxide ceramic powder causes microscopic variations in sintered body density or crystal grain size, which causes a significant deterioration of the physical properties of the sintered body, especially the bending strength. did. Therefore, especially when attempting to obtain a sintered body with high strength and reliability, it is important that the mixture does not contain aggregated particles of non-oxide ceramic powder. The present invention eliminates the above-mentioned drawbacks and improves the composition by producing a homogeneous mixture of a non-oxide ceramic composition suitable for injection molding in which non-oxide ceramic powder is uniformly dispersed, and then injection-molding this mixture. The object of the present invention is to provide a method for manufacturing a high-strength and homogeneous non-oxide ceramic sintered body by pressureless sintering. According to the present invention, a homogeneous mixture mainly consisting of non-oxide ceramic powder, a thermoplastic resin, a lubricant, and at least one of a sintering aid and a plasticizer is molded into a desired shape by injection molding. After that, the thermoplastic resin, the lubricant, and the plasticizer are removed by volatilization and decomposition by heating the green body to obtain a defatted green body, and then the defatted green body is fired. In the method for producing a non-oxide ceramic sintered body, the thermoplastic resin added to the homogeneous mixture to coat each non-oxide ceramic powder,
At least one of acrylic acid and methacrylic acid is 1 to 5 parts by weight, and acrylic acid ester is 30 to 30 parts by weight.
Using a material whose main component is a copolymer of 85 parts by weight and 10 to 69 parts by weight of methacrylic acid ester, and the homogeneous mixture mainly consisting of thermoplastic resin-coated non-oxide ceramic powder,
Mix in advance in a dispersion medium and perform a uniform dispersion treatment, then rapidly cool to a temperature lower than the melting point of the dispersion medium to freeze it, and then sublimate and dry the dispersion medium in the frozen product under reduced pressure. The above object can be achieved by a method for producing a non-oxide ceramic sintered body characterized by the following. Next, the present invention will be explained in detail. As mentioned above, it is important that the non-oxide ceramic powder in the non-oxide ceramic composition for injection molding be in a uniformly dispersed state and that its surface be uniformly coated with the thermoplastic resin. ,
Hitherto, there has been no known suitable method for uniformly dispersing the extremely fine non-oxide ceramic powder used in the present invention and for uniformly coating the surface of the powder with thermoplastic resin. The present inventors conducted various studies to uniformly disperse non-oxide ceramic powder and uniformly coat the surface with thermoplastic resin. After the dispersion medium is mixed and uniformly dispersed, the dispersion medium is rapidly cooled to a temperature lower than the melting point of the dispersion medium and frozen, and then the dispersion medium in the frozen material is sublimated and dried under reduced pressure. We have come up with this idea and completed the present invention. In other words, the extremely fine non-oxide ceramic powder used in the present invention is generally a highly cohesive powder, and the conventional method of simply adding a thermoplastic resin and kneading while heating will not produce a non-oxide ceramic powder. Although it is extremely difficult to loosen the agglomeration of ceramic powder and uniformly coat the surface of the powder with thermoplastic resin, the present inventors added non-oxide ceramic powder and thermoplastic resin to a dispersion medium. By mixing, it is possible to obtain a suspension in an extremely uniform mixed state, and further, by rapidly cooling the suspension to a temperature lower than the melting point of the dispersion medium and freezing it in a short period of time, non-oxide By sublimating and drying the dispersion medium in the frozen material under reduced pressure, heat is applied to the surface of the non-oxide ceramic powder while maintaining a uniformly dispersed state. It is possible to uniformly cover the plastic resin. According to the present invention, at least the non-oxide ceramic powder and the thermoplastic resin in the homogeneous mixture are mixed in advance in a dispersion medium and subjected to a uniform dispersion treatment, and then rapidly cooled to a temperature lower than the melting point of the dispersion medium. The dispersion medium in the frozen product must be sublimated and dried under reduced pressure, but the sintering aid added if necessary is a mixture of non-oxide ceramic powder and thermoplastic. It is advantageous to mix the non-oxide ceramic powder with the resin before mixing it in the dispersion medium. According to the present invention, it is desirable that the suspension subjected to the uniform dispersion treatment is frozen as quickly as possible, and the suspension is placed in an atmosphere maintained at a temperature lower than the melting point of the dispersion medium. It is advantageous to spray and freeze. According to the present invention, it is advantageous for the uniform dispersion treatment to use a dispersion device capable of applying a strong shearing force, such as a vibration mill, an attritor, a ball mill, a colloid mill, or a high-speed mixer. According to the present invention, the freeze-dried mixture as described above is put into a mixer that can heat the inside of the container, is sufficiently kneaded while being heated to a temperature of about 150 to 200 degrees Celsius, and is then cooled and solidified. The mixture is then crushed and sized to prepare a homogeneous mixture for injection molding. As the mixer capable of heating the inside of the container, for example, a Labo Plastomill mixer can be advantageously used. Note that the lubricant and plasticizer can be advantageously mixed by either a method in which they are added to the dispersion medium and mixed, or a method in which they are added and mixed at the time of heating and kneading after drying and removing the dispersion medium. be able to. According to the present invention, the dispersion medium has a melting point of −5 to
It is advantageous to use a temperature within the range of 15°C, and at least one selected from benzene and cyclohexane is particularly preferred. According to the present invention, the amount of the dispersion medium to be blended is preferably at least 200 parts by weight per 100 parts by weight of the non-oxide ceramic powder. The reason for this is that if the blending amount of the dispersion medium is less than 200 parts by weight, the viscosity of the suspension is high and it is difficult to sufficiently disperse the non-oxide ceramic powder. This is because it is difficult to uniformly cover the resin. Considering the purpose of obtaining a uniformly mixed suspension, it is advantageous to have as much dispersion medium as possible; however, if it is too large, the time required for freeze-drying will be long and This is not economical since the production capacity of the composition per unit equipment is reduced, so it is advantageous for the amount to be blended within the range of 300 to 1000 parts by weight. According to the present invention, the thermoplastic resin may include ethyl cellulose, ABS, acrylic acid resin, hydroxypropyl cellulose, polyethylene, polypropylene, cellulose acetate, nylon, polyvinyl butyral, ethylene, acrylic copolymer, cellulose acetate butyrate, polystyrene,
Polysulfone, polyethylene glycol, polyethylene oxide, etc. can be used, but among them, acrylic acid resin consisting of at least one polymer selected from acrylic acid, methacrylic acid and derivatives thereof is preferable. preferable. The derivatives of acrylic acid are preferably acrylic esters, such as methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, Acrylic acid-
sec-butyl, tert-butyl acrylate, n-amyl acrylate, iso-amyl acrylate,
acrylic acid-sec-amyl, acrylic acid-tert-
It is advantageous to use amyl, hexyl acrylate, cyclohexyl acrylate, octyl acrylate, nonyl acrylate, decyl acrylate, dodecyl acrylate, furfuryl acrylate, glycidyl acrylate, 2-ethylhexyl acrylate, among others Ethyl acrylate, n-propyl acrylate, iso-propyl acrylate,
N-butyl acrylate and 2-ethylhexyl acrylate are most suitable. The derivatives of methacrylic acid are preferably methacrylic esters, such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, iso-amyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, octyl methacrylate, dodecyl methacrylate, furfuryl methacrylate, methacrylic acid Preference is given to using glycidyl, 2-hydroxyethyl methacrylate, ethylene glycol, dimethacrylate, β-methoxyethyl methacrylate, in particular n-butyl methacrylate, iso-methacrylate.
Butyl is the best. According to the present invention, the thermoplastic resin contains at least one of acrylic acid and methacrylic acid.
It is most preferable that the main component is a copolymer of 5 parts by weight, 30 to 85 parts by weight of acrylic ester, and 10 to 69 parts by weight of methacrylic ester. The glass transition temperature and decomposition temperature of the above-mentioned copolymers of acrylic acid, methacrylic acid, and their derivatives are compared with other conventionally widely used organic resins such as polystyrene, polypropylene, polyethylene, etc., and the results are as follows. It is shown in Table 1.
【表】
第１表からわかるように、ポリスチレンを除く
従来の樹脂ならびに本発明の共重合体はガラス転
移温度が低く流動性が良好である。一方、ポリス
チレンは本発明の共重合体と熱分解温度が近似し
ているが、他の２種は格段に揮発分解温度が高
く、脱脂に要する時間が長くかかる欠点を有して
いる。したがつて、本発明に用いる共重合体はガ
ラス転移温度および揮発分解温度の点で本発明に
おいて用いる非酸化物セラミツクス粉末に添加す
る場合最も好適な熱可塑性樹脂である。
前記重合体が非酸化物セラミツクス粉末を射出
成形する際に使用する熱可塑性樹脂として極めて
好適である理由をさらに詳しく説明すると、前記
重合体は従来一般的に使用されている他の熱可塑
性樹脂に比較して非酸化物セラミツクス粉末との
なじみが極めて良好で、しかも粉末の凝集を充分
ほぐした状態の混合物となすことが容易であるこ
と、および比較的低温域の非酸化性雰囲気中で速
やかに揮発分解させることができるため、非酸化
物セラミツクス粉末を酸化させることなく容易に
脱脂することのできる効果を有するからである。
本発明によれば、熱可塑性樹脂は前記重合体の
他に補助的にポリスチレン、ポリメタクリル酸メ
チル、ポリエチレン、ポリプロピレン、エチレン
−酢酸共重合体を添加することもできる。しかし
ながら前記添加量を余り多くすると射出成形性が
劣化するため、その添加量は熱可塑性樹脂の合計
100重量部に対して50重量部以下とすることが有
利である。また前記熱可塑性樹脂は200〜400℃の
範囲内で揮発分解するものを使用することが有利
である。
本発明によれば、前記熱可塑性樹脂の配合量は
非酸化物セラミツクス粉末100重量部に対して10
〜45重量部であることが好ましい。その理由は前
記配合量が10重量部より少ないと生成形体に割
れ、ふくれ、変形等が生じ易いからであり、一方
45重量部より多いと脱脂後の生成形体密度が低く
なるため高密度の焼結体を得ることが困難になる
からであり、なかでも15〜40重量部の範囲内でよ
り好適な結果が得られる。
本発明によれば、前記非酸化物セラミツクス粉
末としては例えば炭化珪素、炭化ホウ素、炭化ア
ルミニウム、炭化タングステン、炭化チタン、炭
化タンタル、炭化ジルコニウム、窒化珪素、窒化
ホウ素、窒化アルミニウム、窒化チタン、窒化タ
ンタル、窒化ジルコニウムより選ばれるいずれか
少なくとも１種であることが好ましく、なかでも
炭化珪素粉末を使用する場合には８〜50m2/ｇの
比表面積を有するものであることが好ましく、ま
た窒化珪素粉末を使用する場合には１〜50m2/ｇ
の比表面積を有するものであることが有利であ
る。
なお、本発明の方法は、前記非酸化物セラミツ
クス粉末として挙げた炭化物および窒化物の他に
サイアロン粉末、金属珪素粉末あるいは各種酸化
物粉末の射出成形に適用することもできる。
本発明によれば、焼結助剤は非酸化物セラミツ
クス粉末の種類および焼結方法の違いによつて
種々異なるものが使用される。
前記非酸化物セラミツクス粉末として炭化物セ
ラミツクス粉末を使用して常圧焼結する場合に添
加される焼結助剤は通常高密化助剤あるいは炭素
質添加剤のうちいずれか少なくとも１種である。
前記高密化助剤は炭化物セラミツクス粉末とし
て例えば炭化珪素粉末を使用する場合には、主と
してホウ素含有添加剤を使用することが有利であ
り、その他にベリリウム、アルミニウム等を含有
する添加剤も高密化助剤として使用することがで
きる。前記ホウ素含有添加剤としては、例えばホ
ウ素あるいは炭化ホウ素から選ばれる少なくとも
１種をホウ素含有量に換算して炭化珪素粉末100
重量部に対して0.1〜3.0重量部添加することが有
利である。
前記炭素質添加剤としては焼結開始時に炭素の
状態で存在するものであれば使用することがで
き、例えばフエノール樹脂、リグニンスルホン酸
塩、ポリビニルアルコール、コンスターチ、糖
類、コールタールピツチ、アルギン酸塩、ポリフ
エニレン、ポリメチルフエニレンのような各種有
機物質あるいはカーボンブラツク、アセチレンブ
ラツクのような熱分解炭素を有利に使用すること
ができ、特に炭化珪素粉末を焼結する場合には固
定炭素量に換算して炭化珪素粉末100重量部に対
して0.3〜4.0重量部添加することが有利である。
前記非酸化物セラミツクス粉末として炭化物セ
ラミツクス粉末を使用して反応焼結する場合に添
加される焼結助剤は通常目的とする炭化物を構成
する元素の１つである金属元素あるいは炭素質添
加剤のうちいずれか少なくとも１種である。前記
炭素質添加剤としては前述の常圧焼結の際に使用
されるものと同様の物質および各種材料を使用す
ることができる。
前記非酸化物セラミツクス粉末として窒化物セ
ラミツクス粉末を使用して常圧焼結する場合は通
常高密化助剤が焼結助剤として使用される。
窒化物セラミツクス粉末として例えば窒化珪素
粉末を使用する場合には、主として酸化マグネシ
ウム、酸化カルシウム、酸化イツトリウムあるい
は酸化アルミニウムより選ばれる少なくとも１種
を、また窒化アルミニウム粉末を使用する場合に
は主として酸化イツトリウムあるいは二酸化珪素
より選ばれる少なくとも１種を高密化助剤として
使用することが有利である。
前記非酸化物セラミツクス粉末として窒化物セ
ラミツクス粉末を使用して反応焼結する場合に添
加される焼結助剤は通常目的とする窒化物を構成
する元素の１つである金属元素であり、例えば窒
化物セラミツクス粉末として窒化珪素粉末を使用
する場合には金属珪素粉末が焼結助剤として用い
られる。
本発明によれば、前記均一混合物は潤滑剤を含
有する。前記潤滑剤は射出成形時における組成物
の流動性を良好にするとともに金型から成形品を
容易に離型させる効果を有するものであり、その
配合量は非酸化物セラミツクス粉末100重量部に
対して１〜12重量部とすることが好ましい。前記
潤滑剤は通常射出成形の際に使用されるもの例え
ばステアリン酸、ステアリン酸塩、脂肪酸、脂肪
酸アルコール、脂肪酸エステルあるいは炭化水素
系ワツクスより選択されるいずれか少なくとも１
種を使用することが有利である。前記潤滑剤は前
記熱可塑性樹脂の揮発分解温度より低い温度で揮
発分解するものであることが好ましく、特に160
〜180℃の温度範囲内で揮発分解するものが有利
である。
本発明によれば、前記均一混合物は可塑剤を含
有する。前記可塑剤は前記熱可塑性樹脂と相溶性
が良好で樹脂を軟かくする効果を有すると共に均
一混合物に流動性を与え成形性を向上させる効果
を有するものであり、その配合量は非酸化物セラ
ミツクス粉末100重量部に対して１〜８重量部と
することが好ましい。前記可塑剤は通常射出成形
の際に使用されるもの、例えばフタール酸エステ
ル、アジピン酸エステル、高級脂肪酸エステル、
鉱物油あるいは植物油より選択されるいずれか少
なくとも１種を使用することが有利である。前記
可塑剤は前記潤滑剤の揮発分解温度よりも低い温
度で揮発分解するものであることが好ましく、特
に80〜160℃の温度範囲内で揮発分解するものが
有利である。
次に、前述の如くして調製された均一混合物を
使用する非酸化物セラミツクス焼結体の製造方法
について述べる。
本発明によれば、前記均一混合物は所望の形状
の生成形体に成形される。前記生成形体の成形は
従来公知の射出成形法を適用して行なうことがで
きる。前記射出成形法によれば通常160〜210℃に
加熱された混合物が油圧プランジヤーあるいは往
復スクリユー装置によりスプルー、ランナー、ゲ
ートを通して約20〜30℃の温度に維持された金型
の中へ約700〜1400Kg／cm2の圧力で注入される。
しかしながら、本発明によれば、前記金型の温
度は約20〜70℃の範囲内に維持することが有利で
あり、なかでも25〜35℃の範囲内で最も好適な結
果が得られれる。また、本発明によれば、前記金
型の中へ注入するための圧力は約500〜700Kg／cm2
と前記通常使用されている圧力よりも低い範囲内
とすることができる。
なお、前記生成形体の成形方法としては、通常
の射出成形法の他に同じく射出成形手段が含まれ
るトランスフアー成形法を使用することもでき
る。
前述の如くして金型中に注入された混合物は金
型中で約１〜60秒間放置され、硬化した生成形体
として取出される。
次いで、前記生成形体は加熱され生成形体中の
熱可塑性樹脂、潤滑剤および可塑剤は揮発分解に
よつて除去され、脱脂生成形体となる。前記脱脂
処理は通常非酸化性雰囲気中で行なうことが有利
であり、例えばアルゴン、ヘリウム、窒素等のガ
ス雰囲気中で行なう場合に良い結果が得られる。
本発明によれば、前記生成形体の脱脂処理時に
おける昇温スケジユールは生成形体の大きさと容
積に依存し、特に生成形体の厚みに左右される
が、常温から成形時の温度までは約30℃／hrある
いは僅かにそれ以上の割合で昇温し、成形時の温
度以上では約５〜20℃／hrの速度で昇温し、最終
的に約400〜600℃まで昇温して脱脂することが有
利である。前記脱脂処理における昇温速度は余り
速くすると生成形体に亀裂、割れ、ふくれ、陥没
などが生ずるためなるべく長時間かけてゆつくり
行なうことが有利であり、必要に応じて前述の昇
温スケジユールよりもさらにゆつくり昇温するこ
ともできる。
本発明によれば、前記脱脂生成形体は焼結炉内
へ装入され、焼結される。前記焼結方法としては
種々の方法を適用することができるが、なかでも
常圧焼結法あるいは反応焼結法のいずれをも有利
に適用することができる。
なお、前記脱脂処理工程と焼結工程は共通の炉
を使用して行なうことも可能であるが、前者の脱
脂処理工程における昇温速度は極めて遅くする必
要があり、しかも前記脱脂処理は約400〜600℃と
比較的低い温度領域で完了するのに対して、後者
の焼結工程における昇温速度は前者の脱脂処理工
程のように遅くする必要はなく、また焼結温度は
焼結方法によつてそれぞれ異なるが、通常1500℃
以上と極めて高い温度領域であり、しかも雰囲気
制御が極めて重要で高い密閉性が要求される。し
たがつて、前記脱脂処理工程と焼結工程はそれぞ
れの用途に適した別々の炉を使用することが有利
である。
次に本発明を実施例について説明する。
実施例 １
非酸化物セラミツクス粉末としては特公昭55−
40527号公報に記載の主としてβ型結晶よりなる
炭化珪素の製造方法により製造し、さらに精製、
粒度分級した炭化珪素微粉を使用した。前記炭化
珪素微粉は96.0重量％がβ型結晶よりなり、0.35
重量％の遊離炭素、0.32重量％の遊離シリカを含
有し、17.9m2/ｇの比表面積を有していた。
焼結助剤は市販の200メツシユ炭化ホウ素粒を
粉砕し粒度分級して比表面積を22.0m2/ｇに調製
した炭化ホウ素粉末および平均粒径が約210Å、
比表面積が127m2/ｇのオイルフアーネスブラツク
を使用した。
前記炭化珪素粉末500ｇと前記炭化ホウ素粉末
6.5ｇと前記オイルフアーネスブラツク10ｇとの
混合物に対し、アセトン800mlを添加して２時間
ボールミル混合を行なつた後混合物スラリーを乾
燥し均一混合物を得た。
前記均一混合物に対し、メタクリル酸−iso−
ブチル48重量部とアクリル酸−ｎ−ブチル50重量
部とアクリル酸２重量部との共重合体で分子量が
約２万の樹脂50.0ｇとポリスチレン33.3ｇとエチ
レン−酢酸ビニル共重合体（酢酸ビニル含有量が
28重量％）16.7ｇとステアリン酸24.0ｇとジエチ
ルフタレート12.0ｇとベンゼン2500mlを添加し、
振動ミルを使用して６時間分散処理を行なつた。
前記振動ミルより懸濁液を振動ミルの運転を行な
いながら排出し、−50℃に維持された容器内へ装
入して凍結物を得た。前記懸濁液が排出されてか
ら凍結される迄の時間は約20秒間であつた。つい
で前記凍結物を0.01〜20mmHg、０〜−５℃に維
持された容器中に装入して凍結乾燥を行なつた。
この乾燥物を180℃に維持されたラボプラストミ
ル中で約30分間加熱混合し、ついで冷却し破砕し
て粒状化し、６メツシユの篩を通して射出成形用
均一混合物を得た。
成形はプランジヤー式の射出成形機を使用して
行なつた。加熱筒の温度は約180℃、金型の温度
は30℃、射出所要時間は２秒、射出圧力は620
Kg／cm2の条件で射出成形した。生成形体は金型中
で約３〜５秒間保持した後取り出した。なお、生
成形体の総重量は15.5ｇであつた。
生成形体は第１図に示す如き形状で４段差を有
する板状製品であつて、各段における充填性も均
一であつて、巣、割れ、亀裂等の欠陥もなく、か
つ表面性状も極めて良好であつた。
前記生成形体を脱脂炉に装入し、アルゴンガス
気流中で常温から400℃まで15℃／hrの割合で昇
温して脱脂処理を行ない、脱脂生成形体を得た。
ついで、前記脱脂生成形体をタンマン型焼結炉
に装入し、アルゴンガス気流中で焼結した。焼結
は最高温度2100℃で30分間保持した。
得られた焼結体は3.12ｇ／cm2の密度を有してい
た。この焼結体を３×３×30mmの棒状に加工し、
最終的に2μmのダイヤモンド砥粒で研磨仕上げ
し、スパン20mm、クロスヘツドスピード0.5mm／
minの条件で３点曲げ強度を測定したところ常温
で68.4Kg／mm2の平均強度を有していた。
実施例２、比較例１
実施例１と同様の配合であるが、第２表に示し
た如くベンゼンの配合量を変えて懸濁液を調製
し、実施例１と同様の操作で焼結体を得た。
得られた焼結体の物性は実施例１に示したと同
様の方法で測定し、第２表に示した。[Table] As can be seen from Table 1, conventional resins other than polystyrene and the copolymer of the present invention have low glass transition temperatures and good fluidity. On the other hand, although polystyrene has a thermal decomposition temperature similar to that of the copolymer of the present invention, the other two types have a disadvantage that their volatile decomposition temperatures are significantly higher and that degreasing takes a long time. Therefore, the copolymer used in the present invention is the most suitable thermoplastic resin when added to the non-oxide ceramic powder used in the present invention in terms of glass transition temperature and volatile decomposition temperature. To explain in more detail why the above polymer is extremely suitable as a thermoplastic resin used when injection molding non-oxide ceramic powder, the above polymer is compatible with other conventionally commonly used thermoplastic resins. Comparatively, it has extremely good compatibility with non-oxide ceramic powder, and it is easy to form a mixture in which powder agglomerations are sufficiently loosened, and it can be quickly mixed in a non-oxidizing atmosphere at a relatively low temperature. This is because the non-oxide ceramic powder can be easily degreased without being oxidized since it can be volatile-decomposed. According to the present invention, in addition to the above-mentioned polymers, polystyrene, polymethyl methacrylate, polyethylene, polypropylene, or ethylene-acetic acid copolymer may be added to the thermoplastic resin as an auxiliary. However, if the amount added is too large, the injection moldability will deteriorate, so the amount added should be the total amount of the thermoplastic resin.
It is advantageous to use less than 50 parts by weight per 100 parts by weight. Further, it is advantageous to use a thermoplastic resin that evaporates and decomposes within the range of 200 to 400°C. According to the present invention, the blending amount of the thermoplastic resin is 10 parts by weight per 100 parts by weight of the non-oxide ceramic powder.
Preferably, it is 45 parts by weight. The reason for this is that if the blending amount is less than 10 parts by weight, cracking, blistering, deformation, etc. are likely to occur in the formed body;
This is because if the amount is more than 45 parts by weight, the density of the formed body after degreasing will be low and it will be difficult to obtain a high-density sintered body.Among these, more favorable results can be obtained within the range of 15 to 40 parts by weight. It will be done. According to the present invention, the non-oxide ceramic powder includes, for example, silicon carbide, boron carbide, aluminum carbide, tungsten carbide, titanium carbide, tantalum carbide, zirconium carbide, silicon nitride, boron nitride, aluminum nitride, titanium nitride, tantalum nitride. , zirconium nitride, and especially when using silicon carbide powder, it is preferably one having a specific surface area of 8 to 50 m 2 /g, and silicon nitride powder 1 to 50m 2 /g when using
Advantageously, it has a specific surface area of . The method of the present invention can also be applied to injection molding of sialon powder, metallic silicon powder, or various oxide powders in addition to the carbides and nitrides mentioned above as the non-oxide ceramic powder. According to the present invention, different sintering aids are used depending on the type of non-oxide ceramic powder and the sintering method. When carbide ceramic powder is used as the non-oxide ceramic powder and is sintered under pressure, the sintering aid added is usually at least one of a densification aid and a carbonaceous additive. When using silicon carbide powder as the carbide ceramic powder, it is advantageous to mainly use boron-containing additives as the densification aid, and additives containing beryllium, aluminum, etc. may also be used as the densification aid. It can be used as an agent. As the boron-containing additive, for example, at least one selected from boron and boron carbide is added to silicon carbide powder in terms of boron content of 100%.
It is advantageous to add from 0.1 to 3.0 parts by weight. As the carbonaceous additive, any substance that exists in a carbon state at the start of sintering can be used, such as phenolic resin, lignin sulfonate, polyvinyl alcohol, corn starch, saccharide, coal tar pitch, alginate, Various organic substances such as polyphenylene and polymethylphenylene or pyrolytic carbon such as carbon black and acetylene black can be advantageously used, especially when converting into fixed carbon amount when sintering silicon carbide powder. It is advantageous to add 0.3 to 4.0 parts by weight per 100 parts by weight of silicon carbide powder. The sintering aid added when performing reaction sintering using carbide ceramic powder as the non-oxide ceramic powder is usually a metal element that is one of the elements constituting the target carbide or a carbonaceous additive. At least one of these. As the carbonaceous additive, substances similar to those used in the above-mentioned pressureless sintering and various materials can be used. When nitride ceramic powder is used as the non-oxide ceramic powder and is sintered under pressure, a densification aid is usually used as the sintering aid. For example, when silicon nitride powder is used as the nitride ceramic powder, at least one selected from magnesium oxide, calcium oxide, yttrium oxide, or aluminum oxide is used, and when aluminum nitride powder is used, yttrium oxide or aluminum oxide is mainly used. It is advantageous to use at least one selected from silicon dioxide as a densification aid. The sintering aid added when performing reaction sintering using nitride ceramic powder as the non-oxide ceramic powder is usually a metal element that is one of the elements constituting the target nitride, for example. When using silicon nitride powder as the nitride ceramic powder, metallic silicon powder is used as a sintering aid. According to the invention, said homogeneous mixture contains a lubricant. The lubricant has the effect of improving the fluidity of the composition during injection molding and making it easier to release the molded product from the mold, and the amount of the lubricant is 100 parts by weight of the non-oxide ceramic powder. The amount is preferably 1 to 12 parts by weight. The lubricant is at least one selected from those commonly used in injection molding, such as stearic acid, stearate, fatty acids, fatty acid alcohols, fatty acid esters, and hydrocarbon waxes.
It is advantageous to use seeds. The lubricant is preferably one that volatilizes and decomposes at a temperature lower than the volatilization decomposition temperature of the thermoplastic resin, particularly 160
Preference is given to those which volatile decompose within a temperature range of ~180°C. According to the invention, said homogeneous mixture contains a plasticizer. The plasticizer has good compatibility with the thermoplastic resin, has the effect of softening the resin, and also has the effect of imparting fluidity to the homogeneous mixture and improving moldability. The amount is preferably 1 to 8 parts by weight per 100 parts by weight of powder. The plasticizers are those commonly used in injection molding, such as phthalate esters, adipate esters, higher fatty acid esters,
It is advantageous to use at least one selected from mineral oils and vegetable oils. The plasticizer is preferably one that volatilizes and decomposes at a temperature lower than the volatilization and decomposition temperature of the lubricant, particularly preferably one that volatilizes and decomposes within a temperature range of 80 to 160°C. Next, a method for manufacturing a non-oxide ceramic sintered body using the homogeneous mixture prepared as described above will be described. According to the invention, the homogeneous mixture is molded into a desired shaped product. The molding of the formed body can be performed by applying a conventionally known injection molding method. According to the injection molding method, a mixture heated to 160 to 210 degrees Celsius is usually passed through sprues, runners, and gates by a hydraulic plunger or reciprocating screw device into a mold maintained at a temperature of about 20 to 30 degrees Celsius. Injected at a pressure of 1400Kg/ cm2 . However, according to the invention, it is advantageous to maintain the temperature of the mold in the range of approximately 20-70°C, with the most favorable results being obtained within the range of 25-35°C. Further, according to the present invention, the pressure for injecting into the mold is about 500 to 700 Kg/cm 2
and can be within a range lower than the above-mentioned normally used pressure. In addition to the usual injection molding method, a transfer molding method that also includes injection molding means can also be used as a method for molding the formed body. The mixture injected into the mold as described above is left in the mold for about 1 to 60 seconds and removed as a hardened product. Next, the green body is heated, and the thermoplastic resin, lubricant, and plasticizer in the green body are removed by volatile decomposition, resulting in a defatted green body. It is usually advantageous for the degreasing treatment to be carried out in a non-oxidizing atmosphere, for example good results are obtained when carried out in a gas atmosphere such as argon, helium, nitrogen or the like. According to the present invention, the temperature increase schedule during the degreasing treatment of the formed body depends on the size and volume of the formed body, and particularly on the thickness of the formed body, but the temperature from normal temperature to the temperature at the time of molding is about 30°C. /hr or slightly higher, and above the temperature during molding, increase the temperature at a rate of about 5 to 20℃/hr, and finally raise the temperature to about 400 to 600℃ for degreasing. is advantageous. If the temperature increase rate in the degreasing treatment is too high, cracks, cracks, blisters, depressions, etc. will occur in the formed body, so it is advantageous to carry out the temperature increase slowly for as long as possible. It is also possible to raise the temperature more slowly. According to the present invention, the degreased shaped body is charged into a sintering furnace and sintered. Various methods can be used as the sintering method, and among them, either the pressureless sintering method or the reaction sintering method can be advantageously applied. Note that the degreasing process and the sintering process can be performed using a common furnace, but the temperature increase rate in the former degreasing process must be extremely slow, and the degreasing process requires approximately 400 While the process is completed at a relatively low temperature of ~600℃, the temperature increase rate in the latter sintering process does not need to be as slow as in the former degreasing process, and the sintering temperature depends on the sintering method. It varies depending on the case, but usually 1500℃
This is an extremely high temperature range, and atmosphere control is extremely important and high airtightness is required. Therefore, it is advantageous for the degreasing process and the sintering process to use separate furnaces suitable for their respective uses. Next, the present invention will be explained with reference to examples. Example 1 As a non-oxide ceramic powder,
Produced by the method for producing silicon carbide mainly composed of β-type crystals described in Publication No. 40527, further purified,
Particle size classified silicon carbide fine powder was used. The silicon carbide fine powder consists of 96.0% by weight of β-type crystals, and 0.35% by weight
It contained % free carbon by weight, 0.32% free silica by weight, and had a specific surface area of 17.9 m 2 /g. The sintering aid is boron carbide powder prepared by crushing and classifying commercially available 200 mesh boron carbide particles to have a specific surface area of 22.0 m 2 /g, and an average particle size of approximately 210 Å.
An oil furnace black with a specific surface area of 127 m 2 /g was used. 500g of the silicon carbide powder and the boron carbide powder
To a mixture of 6.5 g and 10 g of the oil furnace black, 800 ml of acetone was added and mixed in a ball mill for 2 hours, and then the mixture slurry was dried to obtain a homogeneous mixture. To the homogeneous mixture, methacrylic acid -iso-
A copolymer of 48 parts by weight of butyl, 50 parts by weight of n-butyl acrylate, and 2 parts by weight of acrylic acid with a molecular weight of approximately 20,000 g, 33.3 g of polystyrene, and an ethylene-vinyl acetate copolymer (vinyl acetate). The content is
28% by weight) 16.7g, stearic acid 24.0g, diethyl phthalate 12.0g and benzene 2500ml,
Dispersion treatment was carried out for 6 hours using a vibration mill.
The suspension was discharged from the vibration mill while operating the vibration mill, and charged into a container maintained at -50°C to obtain a frozen product. The time from when the suspension was discharged until it was frozen was about 20 seconds. Then, the frozen product was placed in a container maintained at 0.01 to 20 mmHg and 0 to -5°C, and freeze-dried.
This dried product was heated and mixed for about 30 minutes in a laboplasto mill maintained at 180°C, then cooled, crushed and granulated, and passed through a 6-mesh sieve to obtain a homogeneous mixture for injection molding. Molding was carried out using a plunger type injection molding machine. The temperature of the heating cylinder is approximately 180℃, the temperature of the mold is 30℃, the injection time is 2 seconds, and the injection pressure is 620℃.
Injection molding was performed under the condition of kg/cm 2 . The resulting shape was held in the mold for about 3-5 seconds and then removed. The total weight of the formed body was 15.5 g. The resulting product is a plate-like product with four steps as shown in Figure 1, and the filling properties in each step are uniform, there are no defects such as cavities, cracks, and cracks, and the surface quality is extremely good. It was hot. The green body was placed in a degreasing furnace, and the temperature was raised from room temperature to 400°C at a rate of 15°C/hr in an argon gas flow to perform a degreasing treatment to obtain a defatted body. Then, the degreased shaped body was placed in a Tammann type sintering furnace and sintered in an argon gas stream. Sintering was maintained at a maximum temperature of 2100°C for 30 minutes. The obtained sintered body had a density of 3.12 g/cm 2 . Process this sintered body into a rod shape of 3 x 3 x 30 mm,
Finally, it is polished with 2μm diamond abrasive grains, with a span of 20mm and a crosshead speed of 0.5mm/
When the three-point bending strength was measured under the conditions of min., it had an average strength of 68.4 Kg/mm 2 at room temperature. Example 2, Comparative Example 1 A suspension was prepared using the same formulation as in Example 1, but with a different amount of benzene as shown in Table 2, and a sintered body was prepared in the same manner as in Example 1. I got it. The physical properties of the obtained sintered body were measured in the same manner as shown in Example 1, and are shown in Table 2.
【表】
第２表に示した結果よりわかるように、ベンゼ
ンの配合量が少ないと長時間分散処理を施しても
焼結体の物性を向上させることが困難であるが、
本実施例によれば比較的短時間の分散処理で焼結
体の物性を著しく向上させることができる。
実施例３、比較例２
実施例１と同様の配合であるが、第３表に示し
た如く熱可塑性樹脂、潤滑剤および可塑剤の配合
量を変えて実施例１と同様の操作を行ない焼結体
を得た。
得られた焼結体の物性は実施例１に示したと同
様の方法で測定し、第３表に示した。[Table] As can be seen from the results shown in Table 2, if the amount of benzene blended is small, it is difficult to improve the physical properties of the sintered body even if the dispersion treatment is performed for a long time.
According to this example, the physical properties of the sintered body can be significantly improved with a relatively short dispersion treatment. Example 3, Comparative Example 2 The formulation was the same as in Example 1, but the blending amounts of the thermoplastic resin, lubricant, and plasticizer were changed as shown in Table 3, and the same operation as in Example 1 was carried out. Obtained a body. The physical properties of the obtained sintered body were measured in the same manner as shown in Example 1, and are shown in Table 3.
【表】
第３表に示した結果よりわかるように、比較例
２−１の熱可塑性樹脂の配合量が多い場合には、
脱脂生成形体の密度が低く、焼結時の収縮性に劣
り、高密度の焼結体を得ることが困難であつた。
また比較例２−２の熱可塑性樹脂の配合量が少な
い場合には、射出成形性が著しく劣り金型内に流
れむらが生じ、均一混合物の充填されていない箇
所が段差のもつとも薄い段に生じた。さらに比較
例２−３の比較例２−２に比較して潤滑剤および
可塑剤の添加量を多くして射出性を向上させた場
合には脱脂処理時に生成形体が変形し、歪を生じ
た。
実施例 ４
実施例１に示したと同様であるが、熱可塑性樹
脂としてメタクリル酸−iso−ブチル69重量部と
アクリル酸エチル26重量部とメタクリル酸５重量
部との共重合体で分子量が約３万の樹脂52.0ｇと
ポリスチレン33.0ｇとエチレン−酢酸ビニル共重
合体（酢酸ビニル含有量が40重量％）14.0ｇとを
使用し、潤滑剤としてステアリン酸17.1ｇとワツ
クス（融点66〜68℃）3.1ｇとを使用し、さらに
可塑剤としてジメチルフタレート5.8ｇとを使用
して均一分散処理を行なつた後、懸濁液を−50℃
に維持された容器中に噴霧して平均粒径が約0.13
mmの顆粒状凍結物を得た。ついで前記顆粒状凍結
物を実施例１と同様の操作で凍結乾燥し、生成形
体を得た。
生成形体は第２図に示す如き糸巻き型の形状
で、巣、割れ、亀裂等の欠陥もなく、かつ表面性
状も優れていた。なお、前記生成形体の総重量は
12.5ｇであつた。
前記生成形体を脱脂炉に装入し、アルゴンガス
気流中で常温から160℃までは約70℃／hrの割合
で昇温し、さらに160℃から450℃までは約15℃／
hrの割合で昇温して脱脂処理を行ない、脱脂生成
形体を得た。
ついで、前記生成形体を実施例１と同様に焼結
し、焼結体を得た。
得られた焼結体は3.13ｇ/cm3の密度を有してお
り、実施例１と同様にして測定した平均強度は
70.8Kg／mm2であつた。
実施例 ５
実施例１に示したと同様の配合および操作であ
るが、非酸化物セラミツクス粉末として、市販の
α型炭化珪素粉末（GC＃6000）をさらに粉砕し、
精製、粒度分級した炭化珪素粉末であつて、0.35
重量％の遊離炭素、0.31重量％の遊離シリカを含
有し、16.2m2/ｇの比表面積を有する炭化珪素粉
末を使用し、メタクリル酸−ｎ−ブチル60重量部
とアクリル酸エチル36重量部とメタクリル酸４重
量部との共重合体で分子量が約２万５千の樹脂
130ｇとステアリン酸26.0ｇとアジピン酸ジメチ
ル10.0ｇとを使用して生成形体を作成した。
前記生成形体は第２図に示す如き形状で、巣、
割れ、亀裂等の欠陥も観察されず、かつ表面性状
も良好であつた。
ついで、前記生成形体を実施例４と同様の操作
で脱脂し、さらに実施例１と同様の操作であるが
最高温度を2300℃に変更して焼結体を得た。
得られた焼結体の密度は3.10ｇ/cm3で、実施例
１と同様にして測定した平均強度は57.1Kg／mm2で
あつた。
実施例 ６
純度が98.2重量％で比表面積が7.3m2/ｇの窒化
珪素粉末200ｇと平均粒径が0.8μmの酸化イツト
リウム6.0ｇとの均一混合物に対し、メタクリル
酸−iso−ブチル50重量部とアクリル酸−ｎ−ブ
チル48重量部とメタクリル酸２重量部との共重合
体で分子量が約２万の樹脂20.0ｇとポリスチレン
12.0ｇとエチレン−酢酸ビニル共重合体（酢酸ビ
ニル含有量28重量％）6.0ｇとワツクス（融点66
〜68℃）6.0ｇとステアリン酸6.0ｇとジエチルフ
タレート4.0ｇとを添加し、実施例１と同様の操
作で第２図に示す如き生成形体を製造し、脱脂処
理を行なつた。
ついで、前記脱脂生成形体を焼結炉に装入し、
窒素ガス気流中で焼結した。焼結は最高温度1650
℃で４時間保持した。
得られた焼結体の密度は3.15ｇ/cm3で、実施例
１と同様にして測定した平均速度は84.7Kg／mm2で
あつた。
以上述べた如く、本発明方法によれば、射出成
形性に極めて優れた非酸化物セラミツクス粉末と
熱可塑性樹脂との均一混合物を短時間でしかも容
易に製造することができ、この均一混合物を使用
して密度あるいは結晶粒径等、物性上のミクロ的
なバラツキの極めて少ない高強度でかつ均質な非
酸化物セラミツクス焼結体を製造することがで
き、産業に寄与する効果は極めて大きい。[Table] As can be seen from the results shown in Table 3, when the blending amount of the thermoplastic resin in Comparative Example 2-1 is large,
The density of the defatted compact was low and the shrinkability during sintering was poor, making it difficult to obtain a high-density sintered compact.
In addition, when the blending amount of the thermoplastic resin in Comparative Example 2-2 is small, injection moldability is significantly inferior, uneven flow occurs in the mold, and areas where the uniform mixture is not filled appear at the thinnest steps of the step. Ta. Furthermore, when the injection properties were improved by increasing the amount of lubricant and plasticizer added compared to Comparative Example 2-3, the resulting shape was deformed during the degreasing process, causing distortion. . Example 4 The same as shown in Example 1, except that the thermoplastic resin was a copolymer of 69 parts by weight of iso-butyl methacrylate, 26 parts by weight of ethyl acrylate, and 5 parts by weight of methacrylic acid and had a molecular weight of about 3. 52.0g of plastic resin, 33.0g of polystyrene, 14.0g of ethylene-vinyl acetate copolymer (vinyl acetate content: 40% by weight), and 17.1g of stearic acid and wax (melting point 66-68℃) as lubricants. After homogeneous dispersion treatment using 3.1g of dimethyl phthalate and 5.8g of dimethyl phthalate as a plasticizer, the suspension was heated to -50°C.
When sprayed into a container maintained at an average particle size of approximately 0.13
Frozen granules of mm size were obtained. The frozen granules were then freeze-dried in the same manner as in Example 1 to obtain a product. The resulting product had a pincushion shape as shown in FIG. 2, had no defects such as cavities, cracks, and cracks, and had excellent surface properties. In addition, the total weight of the formed body is
It was 12.5g. The formed body was charged into a degreasing furnace, and the temperature was raised at a rate of about 70°C/hr from room temperature to 160°C in an argon gas flow, and then at a rate of about 15°C/hr from 160°C to 450°C.
Degreasing treatment was carried out by raising the temperature at a rate of hr to obtain a defatted product. Then, the green body was sintered in the same manner as in Example 1 to obtain a sintered body. The obtained sintered body had a density of 3.13 g/cm 3 , and the average strength measured in the same manner as in Example 1 was
It was 70.8Kg/ mm2 . Example 5 The formulation and operation were the same as those shown in Example 1, but commercially available α-type silicon carbide powder (GC#6000) was further ground as a non-oxide ceramic powder.
Refined and particle size classified silicon carbide powder with 0.35
A silicon carbide powder containing % free carbon, 0.31% free silica and a specific surface area of 16.2 m 2 /g was used, and 60 parts by weight of n-butyl methacrylate and 36 parts by weight of ethyl acrylate were used. A resin that is a copolymer with 4 parts by weight of methacrylic acid and has a molecular weight of approximately 25,000.
130 g, stearic acid, 26.0 g, and dimethyl adipate, 10.0 g. The generated shape has a shape as shown in FIG. 2, and has a nest,
No defects such as cracks or cracks were observed, and the surface quality was good. Next, the formed body was degreased in the same manner as in Example 4, and a sintered body was obtained in the same manner as in Example 1 except that the maximum temperature was changed to 2300°C. The density of the obtained sintered body was 3.10 g/cm 3 , and the average strength measured in the same manner as in Example 1 was 57.1 Kg/mm 2 . Example 6 50 parts by weight of iso-butyl methacrylate was added to a homogeneous mixture of 200 g of silicon nitride powder with a purity of 98.2% by weight and a specific surface area of 7.3 m 2 /g and 6.0 g of yttrium oxide with an average particle size of 0.8 μm. 20.0 g of a copolymer of 48 parts by weight of n-butyl acrylate and 2 parts by weight of methacrylic acid with a molecular weight of approximately 20,000, and polystyrene.
12.0g and 6.0g of ethylene-vinyl acetate copolymer (vinyl acetate content 28% by weight) and wax (melting point 66
68° C.), 6.0 g of stearic acid, and 4.0 g of diethyl phthalate were added, and the same procedure as in Example 1 was carried out to produce a product as shown in FIG. 2, which was then degreased. Then, the degreased formed body is charged into a sintering furnace,
Sintering was carried out in a nitrogen gas stream. Maximum temperature for sintering is 1650
It was kept at ℃ for 4 hours. The density of the obtained sintered body was 3.15 g/cm 3 , and the average speed measured in the same manner as in Example 1 was 84.7 Kg/mm 2 . As described above, according to the method of the present invention, a homogeneous mixture of non-oxide ceramic powder and thermoplastic resin with extremely excellent injection moldability can be easily produced in a short time, and this homogeneous mixture can be used. As a result, it is possible to produce a high-strength and homogeneous non-oxide ceramic sintered body with very little microscopic variation in physical properties such as density or crystal grain size, which has an extremely large effect on industry.
第１，２，３図はそれぞれ本発明ならびに比較
例により製造した生成形体の４段差の形状を有す
る製品、糸巻き型形状を有する製品および円盤状
を有する製品の斜視図である。
FIGS. 1, 2, and 3 are perspective views of a product having a four-step shape, a product having a pincushion shape, and a product having a disk shape, respectively, manufactured according to the present invention and a comparative example.
Claims (1)
性樹脂、潤滑剤、および焼結助剤もしくは可塑剤
のいずれか少なくとも１種とからなる均一混合物
を、射出成形によつて所望の形状の生成形体に成
形し、その後、この生成形体を加熱して前記熱可
塑性樹脂および潤滑剤ならびに可塑剤をそれぞれ
揮発分解させることによつて除去し、脱脂生成形
体となし、ついでこの脱脂生成形体を焼成して非
酸化物セラミツクス焼結体を製造する方法におい
て、 前記均一混合物の中に添加して各非酸化物セラ
ミツクス粉末を被覆する前記熱可塑性樹脂とし
て、アクリル酸、メタクリル酸のいずれか少なく
とも１種が１〜５重量部、アクリル酸エステルが
30〜85重量部およびメタクリル酸エステルが10〜
69重量部の割合で共重合したものを主成分とする
ものを用い、しかもその熱可塑性樹脂被覆非酸化
物セラミツクス粉末を主体とする前記均一混合物
を、分散媒液中で予め混合し均一分散処理を施
し、その後前記分散媒液の融点より低い温度まで
急冷して凍結させ、ついで前記凍結させた凍結物
中の分散媒液を減圧下で昇華乾燥せしめることを
特徴とする非酸化物セラミツクス焼結体の製造方
法。 ２ 前記分散媒液は、ベンゼン、シクロヘキサン
より選ばれるいずれか少なくとも１種である特許
請求の範囲第１項記載の製造方法。 ３ 前記分散媒液の配合量は非酸化物セラミツク
ス粉末100重量部に対して少なくとも200重量部で
ある特許請求の範囲第１あるいは２項記載の製造
方法。 ４ 前記熱可塑性樹脂の配合量は非酸化物セラミ
ツクス粉末100重量部に対して10〜45重量部の範
囲内である特許請求の範囲第１〜３項のいずれか
１つに記載の製造方法。 ５ 前記非酸化物セラミツクス粉末は、炭化珪
素、炭化ホウ素、炭化アルミニウム、炭化タング
ステン、炭化チタン、炭化タンタル、炭化ジルコ
ニウム、窒化珪素、窒化ホウ素、窒化アルミニウ
ム、窒化チタン、窒化タンタル、窒化ジルコニウ
ムより選ばれる少なくとも１種である特許請求の
範囲第１〜４項のいずれか１つに記載の製造方
法。 ６ 前記非酸化物セラミツクス粉末は、８〜50
m2／ｇの比表面積を有する炭化珪素粉末である特
許請求の範囲第１〜５項のいずれか１つに記載の
製造方法。 ７ 前記非酸化物セラミツクス粉末は、１〜50
m2／ｇの比表面積を有する窒化珪素粉末である特
許請求の範囲第１〜５項のいずれか１つに記載の
製造方法。 ８ 前記潤滑剤は、前記熱可塑性樹脂の揮発分解
温度よりも低い温度で揮発あるいは揮発分解する
ものであつて、その配合量は非酸化物セラミツク
ス粉末100重量部に対して１〜12重量部である特
許請求の範囲第１〜７項のいずれか１つに記載の
製造方法。 ９ 前記可塑剤は、前記潤滑の揮発分解温度より
も低い温度で揮発あるいは揮発分解するものであ
つて、その配合量は非酸化物セラミツクス粉末
100重量部に対して１〜８重量部である特許請求
の範囲第１〜８項のいずれか１つに記載の製造方
法。[Scope of Claims] 1. A homogeneous mixture mainly consisting of non-oxide ceramic powder and at least one of a thermoplastic resin, a lubricant, and a sintering aid or a plasticizer is molded into a desired shape by injection molding. After that, the thermoplastic resin, lubricant, and plasticizer are removed by volatilization and decomposition by heating the formed body to form a defatted shaped body, and then the defatted shaped body is formed into a defatted shaped body. In the method of manufacturing a non-oxide ceramic sintered body by firing, the thermoplastic resin added to the homogeneous mixture to coat each non-oxide ceramic powder includes at least one of acrylic acid and methacrylic acid. 1 to 5 parts by weight of seeds, acrylic ester
30-85 parts by weight and 10-85 parts of methacrylic acid ester
Using a copolymerized product at a ratio of 69 parts by weight, the homogeneous mixture mainly consisting of thermoplastic resin-coated non-oxide ceramic powder is premixed in a dispersion medium and subjected to uniform dispersion treatment. , then rapidly cooled to a temperature lower than the melting point of the dispersion medium to freeze it, and then sublimation-dried the dispersion medium in the frozen material under reduced pressure. How the body is manufactured. 2. The manufacturing method according to claim 1, wherein the dispersion medium is at least one selected from benzene and cyclohexane. 3. The manufacturing method according to claim 1 or 2, wherein the blending amount of the dispersion medium is at least 200 parts by weight per 100 parts by weight of the non-oxide ceramic powder. 4. The manufacturing method according to any one of claims 1 to 3, wherein the blending amount of the thermoplastic resin is within the range of 10 to 45 parts by weight based on 100 parts by weight of the non-oxide ceramic powder. 5. The non-oxide ceramic powder is selected from silicon carbide, boron carbide, aluminum carbide, tungsten carbide, titanium carbide, tantalum carbide, zirconium carbide, silicon nitride, boron nitride, aluminum nitride, titanium nitride, tantalum nitride, and zirconium nitride. The manufacturing method according to any one of claims 1 to 4, which is at least one type. 6. The non-oxide ceramic powder has a particle size of 8 to 50
The manufacturing method according to any one of claims 1 to 5, which is a silicon carbide powder having a specific surface area of m 2 /g. 7 The non-oxide ceramic powder has a 1 to 50
The manufacturing method according to any one of claims 1 to 5, which is a silicon nitride powder having a specific surface area of m 2 /g. 8. The lubricant evaporates or decomposes at a temperature lower than the volatile decomposition temperature of the thermoplastic resin, and the amount thereof is 1 to 12 parts by weight per 100 parts by weight of the non-oxide ceramic powder. A manufacturing method according to any one of claims 1 to 7. 9. The plasticizer is one that volatilizes or decomposes by volatilization at a temperature lower than the volatilization decomposition temperature of the lubricant, and the amount thereof is equal to that of the non-oxide ceramic powder.
The manufacturing method according to any one of claims 1 to 8, wherein the amount is 1 to 8 parts by weight per 100 parts by weight.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58092514A JPS59223266A (en) | 1983-05-27 | 1983-05-27 | Manufacture of non-oxide ceramic sintered body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58092514A JPS59223266A (en) | 1983-05-27 | 1983-05-27 | Manufacture of non-oxide ceramic sintered body |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59223266A JPS59223266A (en) | 1984-12-15 |
| JPH0210790B2 true JPH0210790B2 (en) | 1990-03-09 |
Family
ID=14056424
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58092514A Granted JPS59223266A (en) | 1983-05-27 | 1983-05-27 | Manufacture of non-oxide ceramic sintered body |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59223266A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6221753A (en) * | 1985-07-17 | 1987-01-30 | 三井化学株式会社 | Composition for manufacturing ceramics |
| JP2949586B2 (en) * | 1988-03-07 | 1999-09-13 | 株式会社日立製作所 | Conductive material and manufacturing method thereof |
| JPH0354169A (en) * | 1989-07-20 | 1991-03-08 | Fujitsu Ltd | Degreasing of aluminum nitride green sheet |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5034608A (en) * | 1973-07-13 | 1975-04-03 | ||
| JPS5078609A (en) * | 1973-10-24 | 1975-06-26 |
-
1983
- 1983-05-27 JP JP58092514A patent/JPS59223266A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5034608A (en) * | 1973-07-13 | 1975-04-03 | ||
| JPS5078609A (en) * | 1973-10-24 | 1975-06-26 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59223266A (en) | 1984-12-15 |
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