JPH0537944B2 - - Google Patents
Info
- Publication number
- JPH0537944B2 JPH0537944B2 JP19961183A JP19961183A JPH0537944B2 JP H0537944 B2 JPH0537944 B2 JP H0537944B2 JP 19961183 A JP19961183 A JP 19961183A JP 19961183 A JP19961183 A JP 19961183A JP H0537944 B2 JPH0537944 B2 JP H0537944B2
- Authority
- JP
- Japan
- Prior art keywords
- sintered body
- silicon nitride
- crystal structure
- cutting
- trigonal
- 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
- 229910052581 Si3N4 Inorganic materials 0.000 claims description 50
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 claims description 49
- 239000013078 crystal Substances 0.000 claims description 47
- 238000005245 sintering Methods 0.000 claims description 28
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 14
- 229910052782 aluminium Inorganic materials 0.000 claims description 12
- 150000004767 nitrides Chemical class 0.000 claims description 12
- 239000006104 solid solution Substances 0.000 claims description 12
- 229910052760 oxygen Inorganic materials 0.000 claims description 11
- 239000001301 oxygen Substances 0.000 claims description 10
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 9
- 229910052733 gallium Inorganic materials 0.000 claims description 8
- 229910052757 nitrogen Inorganic materials 0.000 claims description 8
- 229910052791 calcium Inorganic materials 0.000 claims description 7
- 239000011575 calcium Substances 0.000 claims description 7
- 229910052744 lithium Inorganic materials 0.000 claims description 7
- 229910052749 magnesium Inorganic materials 0.000 claims description 7
- 239000011777 magnesium Substances 0.000 claims description 7
- 229910052700 potassium Inorganic materials 0.000 claims description 7
- 229910052712 strontium Inorganic materials 0.000 claims description 7
- 229910052727 yttrium Inorganic materials 0.000 claims description 7
- 239000012535 impurity Substances 0.000 claims description 6
- 229910052747 lanthanoid Inorganic materials 0.000 claims description 6
- 150000002602 lanthanoids Chemical class 0.000 claims description 6
- 239000003607 modifier Substances 0.000 claims description 6
- 229910052796 boron Inorganic materials 0.000 claims description 5
- 229910052706 scandium Inorganic materials 0.000 claims description 5
- 229910052710 silicon Inorganic materials 0.000 claims description 4
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 3
- 239000010703 silicon Substances 0.000 claims description 3
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims description 2
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 2
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims description 2
- 229910052788 barium Inorganic materials 0.000 claims description 2
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 claims description 2
- 239000011591 potassium Substances 0.000 claims description 2
- SIXSYDAISGFNSX-UHFFFAOYSA-N scandium atom Chemical compound [Sc] SIXSYDAISGFNSX-UHFFFAOYSA-N 0.000 claims description 2
- CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 claims description 2
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 claims description 2
- -1 gallium nitrides Chemical class 0.000 claims 1
- 238000005520 cutting process Methods 0.000 description 36
- 239000000463 material Substances 0.000 description 17
- 239000000956 alloy Substances 0.000 description 16
- 229910045601 alloy Inorganic materials 0.000 description 15
- 239000000843 powder Substances 0.000 description 15
- 229910001220 stainless steel Inorganic materials 0.000 description 9
- 239000010935 stainless steel Substances 0.000 description 9
- 230000007423 decrease Effects 0.000 description 8
- 230000000737 periodic effect Effects 0.000 description 8
- 239000000919 ceramic Substances 0.000 description 7
- 239000002245 particle Substances 0.000 description 7
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 6
- 239000007789 gas Substances 0.000 description 6
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 6
- 229910052738 indium Inorganic materials 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 239000011812 mixed powder Substances 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 238000003801 milling Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 239000002904 solvent Substances 0.000 description 4
- 229910052716 thallium Inorganic materials 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 3
- 239000002131 composite material Substances 0.000 description 3
- 238000000280 densification Methods 0.000 description 3
- 239000004033 plastic Substances 0.000 description 3
- 229910052708 sodium Inorganic materials 0.000 description 3
- 239000011734 sodium Substances 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 229910001018 Cast iron Inorganic materials 0.000 description 2
- 229910004298 SiO 2 Inorganic materials 0.000 description 2
- 239000012298 atmosphere Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 239000000839 emulsion Substances 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000000465 moulding Methods 0.000 description 2
- 239000012188 paraffin wax Substances 0.000 description 2
- 238000010298 pulverizing process Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 230000035939 shock Effects 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- BKVIYDNLLOSFOA-UHFFFAOYSA-N thallium Chemical compound [Tl] BKVIYDNLLOSFOA-UHFFFAOYSA-N 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 229910018514 Al—O—N Inorganic materials 0.000 description 1
- 229910001208 Crucible steel Inorganic materials 0.000 description 1
- JOYRKODLDBILNP-UHFFFAOYSA-N Ethyl urethane Chemical compound CCOC(N)=O JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 description 1
- 229910000915 Free machining steel Inorganic materials 0.000 description 1
- GYHNNYVSQQEPJS-UHFFFAOYSA-N Gallium Chemical compound [Ga] GYHNNYVSQQEPJS-UHFFFAOYSA-N 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 101150105594 SCM3 gene Proteins 0.000 description 1
- 229910000746 Structural steel Inorganic materials 0.000 description 1
- 229910001315 Tool steel Inorganic materials 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- 230000002706 hydrostatic effect Effects 0.000 description 1
- 229910000816 inconels 718 Inorganic materials 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 229910000311 lanthanide oxide Inorganic materials 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 150000002926 oxygen Chemical class 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 150000004760 silicates Chemical class 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 229910001247 waspaloy Inorganic materials 0.000 description 1
Description
本発明は、切削工具及び耐摩耗工具に適する高
硬度窒化硅素焼結体であつて、特にα型である三
方晶からなる結晶構造を含有させることによつて
耐熱合金、超耐熱合金及び鋼等の切削工具に最適
な工具部品用窒化硅素焼結体に関する。
従来、窒化硅素はα型（低温型）である三方晶
とβ型（高温型）である六方晶の結晶構造のもの
があり、これらの窒化硅素にAl2O3、AlN、
Y2O3、MgO等の焼結助剤を添加して焼結した焼
結体は、高温で焼結するために高温型の六方晶結
晶構造となる。これらの内、Alを含有したSi−
Al−Ｏ−Ｎ系の化合物又は固溶体は一般にサイ
アロンと称されている。このサイロンは、Si6−
zAlzN8−zOz固溶体として特開昭51−508号公報
で開示され、これは六方晶からなる結晶構造であ
ることから別名β−サイアロンと呼ばれている。
これに対してMx（Si、Al）12（Ｏ、Ｎ）16固溶体が
S.Hampshire達によつて定義され〔Nature、
274、880−82（1978）〕、これは三方晶からなる結
晶構造であることからα−サイアロンと呼ばれて
いる。このような窒化硅素焼結体で三方晶の結晶
構造のものはα−サイアロンのみであり、特に切
削工具や耐摩耗工具等の工具部品用に使用されて
いるのは六方晶の結晶構造からなる窒化硅素焼結
体である。
この六方晶の結晶構造からなる窒化硅素焼結体
は、切削工具として使用するときに被削材が鋳鉄
であるときには良好な切削性能を発揮するけれど
も鋳鉄以外の被削材、特に耐熱合金、超耐熱合金
及び鋼等のように硬くて破断強さの高い材料を切
削するとAl2O3系セラミツクスに比較して耐摩耗
性が極端に劣り切削工具としての使用領域は非常
に狭い範囲に限られてしまうという問題がある。
本発明は、上記のような問題点を解決したもの
で、特に切削工具として使用したときに被削材が
Fe基超耐熱合金、Ni基超耐熱合金、Co基超耐熱
合金、ステンレス、構造用鋼、快削鋼、工具鋼及
び鋳鋼等に対しても耐摩耗性及び耐欠損性を発揮
するような高硬度、高靭性の窒化硅素焼結体を提
供するものである。
本発明の工具部品用窒化硅素焼結体は、窒化硅
素と焼結助剤との混合物を焼結する製造工程にお
いてN2分圧（PN2）の制御によつて低温型の三方
晶から高温型の六方晶への変態を阻止して三方晶
で構成された焼結体を作製することに成功したも
のである。三方晶構造の焼結体は六方晶構造の焼
結体に比べて変形の機構が塑性変形のみであり転
移クリープや拡散クリープによる変形は伴わない
ために高温では相対的に三方晶構造の焼結体の方
が高靭性である。また、三方晶構造の焼結体は六
方晶構造の焼結体よりも熱膨張係数が大きく熱伝
導率が小さいために耐熱衝撃性が劣る傾向にある
ことを確認することによつて本発明を完成した切
削工具及び耐摩耗工具に最適な窒化硅素焼結体で
ある。即ち本発明は窒化硅素を主体とする焼結体
であつて、その焼結体が（Sia、Mb）12（Ox、
Ny）16で示される三方晶（但し、Siは硅素、Ｍは
Al、Ga、Li、Ｋ、Mg、Ca、Sr、Ba、Ｂ、Sc、
Ｙ及びランタノイドの中の少なくとも１種の元素
を表わし、Ｏは酸素、Ｎは窒素を表わす。ａ及び
ｂはそれぞれSiとＭのモル比を表わし、ｘ、ｙは
それぞれ酸素と窒素のモル比を表わし、ａ＋ｂ＝
１、ａ＞０、ｂ＞０、ｘ＋ｙ＝１、ｘ≧０でな
る。）からなる結晶構造を25％以上含有している
工具部品用窒化硅素焼結体である。このような本
発明の工具部品用窒化硅素焼結体は、切削工具と
して使用するときに高硬度にして耐摩耗性の向上
を目的に100％の三方晶結晶構造にすることも考
えられるが切削条件によつては逆に靭性が低下し
て刃先又は切刃に欠損やチツピングが生じて寿命
低下となつて好ましくない場合がある。特に耐熱
合金、超耐熱合金、ステンレス等のように破断強
度の高い被削材を切削するときには切削工具は高
硬度にしてしかも靭性を考慮する必要がある。従
つて、窒化硅素を主体とする焼結体は三方晶から
なる結晶構造35％〜95％含有していることが好ま
しい。
窒化硅素焼結体の結晶構造を三方晶にするには
PN2が重要な役割を果しており、そのためには
Si3N4に固溶し易い周期律表の3b族元素であるホ
ウ素、アルミニウム、インジウム、タリウムの窒
化物及び酸窒化物を有効に作用させることであ
る。この周期律表の3b族元素の窒化物及び酸窒
化物と周期律表の1a、2a、3a族元素の酸化物、
窒化物、酸窒化物とを組合わせて添加すると三方
晶結晶構造の量を調整できることが実験によつて
確認された。この確認事実に基いた本発明の工具
部品用窒化硅素焼結体は、ホウ素、アルミニウ
ム、ガリウム、インジウム、タリウムの窒化物、
酸窒化物又はこれらの相互固溶体の中の少なくと
も１種の結晶構造調整剤２〜17重量％とリチウ
ム、ナトリウム、カリウム、マグネシウム、カル
シウム、ストロンチウム、バリウム、スカンジウ
ム、イツトリウム及びランタノイドの酸化物、窒
化物、酸窒化物又はこれらの相互固溶体の中の少
なくとも１種の焼結助剤１〜16重量％と残り窒化
硅素と不可避不純物とを焼結したものであること
が好ましい。このような本発明の工具部品用窒化
硅素焼結体は、昇温速度、焼結温度、PN2等の製
造条件によつても若干変動するが主として結晶構
造調整剤と焼結助剤との添加比率によつて焼結体
中の三方晶結晶構造の含有量をコントロールでき
る。また、これらの結晶構造調整剤と焼結助剤と
が共有結合性の強い難焼結材料である窒化硅素を
緻密な焼結体にする焼結促進剤的作用もするもの
である。この本発明の工具部品用窒化硅素焼結体
を構成している結晶は、25％以上が三方晶結晶構
造で、その組成は、（Sia、Mb）12（Oy、Ny）16（但
し、Siは硅素、ＭはAl、Ga、Li、Ｋ、Mg、Ca、
Sr、Ba、Ｂ、Sc、Ｙ及びランタノイドの中の少
なくとも１種の金属元素を表わし、Ｏは酸素、Ｎ
は窒素を表わす。ａ及びｂはそれぞれSiとＭのモ
ル比を表わし、ｘ、ｙはそれぞれ酸素、窒素のモ
ル比を表わし、各々ａ＋ｂ＝１、ａ＞０、ｂ＞
０、ｘ＋ｙ＝１、ｘ≧０である。）で示される。
この三方晶の結晶が六方晶のマトリツクスの中に
均一に分散されているもので、三方晶結晶構造以
外の結晶は六方晶の結晶構造であるが製造条件又
は結晶構造調整剤と焼結助剤との各種類の組合わ
せ及びそれらの添加物の比率によつて窒素含有の
結晶珪酸塩となることがある。このように本発明
の工具部品用窒化硅素焼結体は主として三方晶と
六方晶の結晶構造が混在したものである。三方晶
の結晶構造は窒化硅素焼結体の高硬度化及び高温
での耐塑性変形性に寄与して耐摩耗性、耐クリー
プ変形性を高める。三方晶以外の主として六方晶
からなる結晶構造は窒化硅素焼結体の靭性向上に
寄与して耐欠損性を高めている。これらの三方晶
と六方晶の混合比率を最適に組合わせてしかも六
方晶のマトリツクス中に三方晶の硬質相を均一に
分散せしめた窒化硅素焼結体は、破断強度の高い
耐熱合金、超耐熱合金及びステンレス等の切削工
具として最適なものである。
本発明の工具部品用窒化硅素焼結体を作製する
には、出発原料として使用する窒化硅素が三方晶
であるα−窒化硅素の含有率の高い、例えばα率
50％以上のものを使用することが望ましく、その
平均粒径が2μｍ以下の粉末を使用するのがよい。
又、非晶質の窒化硅素を含有したα率50％以上の
窒化硅素粉末を出発原料として使用すると微細な
粉末で焼結も促進される反面窒化硅素粉末の製造
方法によつては酸素を多く含有している場合があ
つて、この酸素量が焼結体中の三方晶結晶構造の
生成を低下させるために酸素含有量には特に注意
が必要である。このような窒化硅素粉末と周期律
表の3b族元素であるＢ、Al、Ga、In、Tlの窒化
物、酸窒化物又はこれらの相互固溶体の中の少な
くとも１種の粉末２〜17重量％と周期律表の1a、
2a、3a族元素であるLi、Na、Ｋ、Mg、Ca、Sr、
Ba、Sc、Ｙ及びランタノイドの酸化物、窒化物、
酸窒化物又はこれらの相互固溶体の中の少なくと
も１種の粉末１〜16重量％とをステンレス製又は
セラミツクス製もしくはステンレス超硬合金、ゴ
ム等を内張りした容器にAl2O3系、Si3N4系、
ZrO2系ボール又はスチールボールもしくは超硬
合金製ボールと共に入れて混合粉砕し、この混合
粉末をカーボン又は黒鉛製の焼結用モールドに詰
めて高周波加圧焼結、通電加圧焼結、ガス加圧焼
結等のホツトプレスによつて焼結して本発明の焼
結体が作製される。また混合粉末を成形モールド
で成形した成形体又はこの成形体を焼結温度より
低い温度で予備焼結した後機械加工した成形体を
真空を含めた非酸化性雰囲気中で普通焼結（無加
圧焼結も含む）又は雰囲気ガスで加圧しながら焼
結して本発明の焼結体が作製される。更に、必要
に応じてこのような方法で１度焼結したものを静
水圧加圧法（HIP）処理を行つて焼結体の緻密化
を促進することもできる。焼結温度は、焼結方法
又は配合成分によつても異なるが1500℃〜1900℃
の温度で相対密度100％近傍の緻密な焼結体が得
られる。本発明の工具部品用窒化硅素焼結体を作
製する場合、出発原料特に窒化硅素粉末中にAl、
Fe等の不純物を微量含んでいたり、窒化硅素粉
末粒子の表面に酸素が吸着してSiO2を形成して
いる場合があり、この内1.2重量％以下のSiO2は
焼結促進及び緻密化に有効に作用するが逆に多過
ぎると三方晶構造の生成を低下させるので出来る
だけ純度の高い窒化硅素粉末を使用することが望
ましい。又製造工程から混入する不純物としては
出発原料粉末の混合粉砕工程から混入する度合が
高く、この粉砕工程では容器及びボールの選定に
よつて不純物の混入を或る程度防ぐことが可能で
あるが粉砕の強化のためにステンレス又は超硬合
金製の容器及びボールを使用することによつて
Fe族金属及び周期律表4a、5a、6a族金属の炭化
物、窒化物、炭窒化物等が不純物として混入する
場合があるものの切削工具、耐摩耗工具として使
用する場合には５重量％以下であれば問題がな
く、更に周期律表の3b族元素である。Ｂ、Al、
Ga、In、Tlの酸化物を焼結助剤として微量添加
することは焼結促進及び緻密化のためによく、特
にAl2O3を微量添加するのは高硬度化と耐摩耗性
の向上にも効果がある。しかしいずれも三方晶の
結晶構造を抑制するので過剰の添加は好ましくな
い。
ここで本発明の工具部品用窒化硅素焼結体の数
値限定した理由について述べる。
結晶構造調整剤
周期律表の3b族元素であるＢ、Al、Ga、In、
Tlの窒化物、酸窒化物又はこれらの相互固溶体
の中の少なくとも１種が２重量％未満では焼結体
の結晶構造中に三方晶が25％未満となり、このた
めに硬さが少し低下して耐摩耗性も劣り、又耐塑
性変形性も低下するために破断強度の高い耐熱合
金、超耐熱合金及びステンレス等の被削材を切削
し難くし、17重量％を超えて多くなると相対的に
窒化硅素が少なくなつて共有結合性が低下し、熱
膨張率が高く、熱伝導率、硬度及びヤング率が低
下するために結晶構造調整剤は２〜17重量％と定
めた。
焼結助剤
Li、Na、Ｋ、Mg、Ca、Sr、Ba、Sc、Ｙ及び
ランタノイドの酸化物、窒化物、酸窒化物又はこ
れらの相互固溶体の中の少なくとも１種が１重量
％未満では焼結性不足になつて焼結体の強度が低
下し、反対に16重量％を超えて多くなると焼結体
の硬度が低下して切削工具として使用したときに
塑性変形を生じるために焼結助剤は１〜16重量％
と定めた。
次に本発明の工具部品用窒化硅素焼結体につい
て実施例に従つて具体的に説明する。
実施例 １
平均粒径1μｍのSi3N4（α率90％）と平均粒径
１〜3μｍの各種粉末を使用して第１表に示した
割合に各試料を配合し、配合したそれぞれの試料
をヘキサン溶媒中WC基超硬合金製ボールと共に
ウレタン内張のステンレス製容器の中で混合粉砕
した。得られた混合粉末から溶媒を蒸発除去後、
BN粉末で被覆したカーボンモールド中に充填
し、N2ガスで炉内を置換後100〜400Kg／cm2の成
形圧力、1700〜1830℃の温度、30〜120分の保持
時間で加圧焼結した。得られた焼結体の諸特性を
第２表に示し、その焼結体の結晶構造及び組成成
分を第３表に示した。
The present invention is a high-hardness silicon nitride sintered body suitable for cutting tools and wear-resistant tools, and in particular contains a crystal structure consisting of α-type trigonal crystals. This article relates to silicon nitride sintered bodies for tool parts that are ideal for cutting tools. Conventionally, silicon nitride has a trigonal α-type (low-temperature type) and a hexagonal β-type (high-temperature type ) crystal structure.
A sintered body sintered by adding a sintering aid such as Y 2 O 3 or MgO has a high-temperature hexagonal crystal structure because it is sintered at a high temperature. Among these, Si- containing Al
Al-O-N based compounds or solid solutions are generally called sialons. This cylon is Si 6 −
It is disclosed in Japanese Patent Application Laid-Open No. 51-508 as a zAlzN 8 -zOz solid solution, and is also called β-Sialon because it has a hexagonal crystal structure.
On the other hand, Mx (Si, Al) 12 (O, N) 16 solid solution
Defined by S.Hampshire et al. [Nature,
274, 880-82 (1978)], it is called α-sialon because it has a trigonal crystal structure. The only silicon nitride sintered body with a trigonal crystal structure is α-Sialon, and the one used for tool parts such as cutting tools and wear-resistant tools has a hexagonal crystal structure. It is a silicon nitride sintered body. This silicon nitride sintered body with a hexagonal crystal structure exhibits good cutting performance when the workpiece material is cast iron when used as a cutting tool, but it can be used in workpiece materials other than cast iron, especially heat-resistant alloys, super When cutting hard materials with high breaking strength such as heat-resistant alloys and steel, the wear resistance is extremely inferior to that of Al 2 O 3 ceramics, and its use as a cutting tool is limited to a very narrow range. There is a problem with this. The present invention solves the above-mentioned problems, especially when used as a cutting tool.
High heat-resistant alloys that exhibit wear resistance and fracture resistance against Fe-based super heat-resistant alloys, Ni-based super heat-resistant alloys, Co-based super heat-resistant alloys, stainless steel, structural steel, free-cutting steel, tool steel, cast steel, etc. The present invention provides a silicon nitride sintered body with high hardness and toughness. The silicon nitride sintered body for tool parts of the present invention is produced by controlling the N2 partial pressure (P N2 ) in the manufacturing process of sintering a mixture of silicon nitride and a sintering aid. They succeeded in producing a sintered body composed of trigonal crystals by preventing the transformation of the mold into hexagonal crystals. Compared to sintered bodies with a hexagonal structure, a sintered body with a trigonal structure has a deformation mechanism that is only plastic deformation and is not accompanied by deformation due to dislocation creep or diffusion creep. The body has higher toughness. Furthermore, the present invention was realized by confirming that sintered bodies with a trigonal structure tend to have a higher thermal expansion coefficient and lower thermal conductivity than sintered bodies with a hexagonal structure, and thus tend to have inferior thermal shock resistance. This silicon nitride sintered body is ideal for finished cutting tools and wear-resistant tools. That is, the present invention is a sintered body mainly composed of silicon nitride, and the sintered body has (Sia, Mb) 12 (Ox,
Ny) trigonal crystal shown by 16 (however, Si is silicon, M is
Al, Ga, Li, K, Mg, Ca, Sr, Ba, B, Sc,
It represents at least one element among Y and lanthanoids, O represents oxygen, and N represents nitrogen. a and b represent the molar ratio of Si and M, respectively, x and y represent the molar ratio of oxygen and nitrogen, respectively, and a+b=
1, a>0, b>0, x+y=1, x≧0. ) is a silicon nitride sintered body for tool parts that contains 25% or more of the crystal structure consisting of The silicon nitride sintered body for tool parts of the present invention may be made into a 100% trigonal crystal structure in order to have high hardness and improve wear resistance when used as a cutting tool. Depending on the conditions, on the other hand, the toughness may decrease, resulting in chipping or chipping of the cutting edge or cutting edge, resulting in a shortened lifespan, which is undesirable. In particular, when cutting work materials with high breaking strength such as heat-resistant alloys, super-heat-resistant alloys, stainless steel, etc., it is necessary to use a cutting tool with high hardness and to take into account toughness. Therefore, the sintered body mainly composed of silicon nitride preferably contains 35% to 95% of the trigonal crystal structure. To make the crystal structure of silicon nitride sintered body trigonal
P N2 plays an important role, and for that purpose
The purpose is to effectively use nitrides and oxynitrides of boron, aluminum, indium, and thallium, which are group 3b elements of the periodic table, which are easily dissolved in Si 3 N 4 . Nitrides and oxynitrides of elements in group 3b of the periodic table, and oxides of elements in groups 1a, 2a, and 3a of the periodic table,
It has been confirmed through experiments that the amount of trigonal crystal structure can be adjusted by adding a combination of nitrides and oxynitrides. Based on this confirmed fact, the silicon nitride sintered body for tool parts of the present invention contains nitrides of boron, aluminum, gallium, indium, thallium,
2 to 17% by weight of at least one crystal structure modifier among oxynitrides or mutual solid solutions thereof and oxides and nitrides of lithium, sodium, potassium, magnesium, calcium, strontium, barium, scandium, yttrium and lanthanides. It is preferable to sinter 1 to 16% by weight of at least one sintering aid selected from , oxynitride, or a mutual solid solution thereof, the remainder silicon nitride, and unavoidable impurities. Such a silicon nitride sintered body for tool parts of the present invention varies slightly depending on manufacturing conditions such as heating rate, sintering temperature, P N2 , etc., but mainly due to the combination of crystal structure modifier and sintering aid. The content of the trigonal crystal structure in the sintered body can be controlled by adjusting the addition ratio. In addition, these crystal structure modifiers and sintering aids act as sintering accelerators to form silicon nitride, which is a difficult-to-sinter material with strong covalent bonds, into a dense sintered body. At least 25% of the crystals constituting the silicon nitride sintered body for tool parts of the present invention have a trigonal crystal structure, and the composition is (Sia, Mb) 12 (Oy, Ny) 16 (However, Si is silicon, M is Al, Ga, Li, K, Mg, Ca,
Represents at least one metal element among Sr, Ba, B, Sc, Y and lanthanoids, O is oxygen, N
represents nitrogen. a and b represent the molar ratio of Si and M, respectively, x and y represent the molar ratio of oxygen and nitrogen, respectively, a+b=1, a>0, b>
0, x+y=1, x≧0. ).
These trigonal crystals are uniformly dispersed in a hexagonal matrix, and crystals other than the trigonal crystal structure have a hexagonal crystal structure, but depending on the manufacturing conditions, crystal structure regulators and sintering aids. Nitrogen-containing crystalline silicates may be obtained depending on the various combinations with and the ratios of their additives. As described above, the silicon nitride sintered body for tool parts of the present invention mainly has a mixture of trigonal and hexagonal crystal structures. The trigonal crystal structure contributes to high hardness of the silicon nitride sintered body and plastic deformation resistance at high temperatures, thereby increasing wear resistance and creep deformation resistance. The crystal structure consisting mainly of hexagonal crystals other than trigonal crystals contributes to improving the toughness of the silicon nitride sintered body and increases its fracture resistance. The silicon nitride sintered body, which has an optimal mixing ratio of trigonal and hexagonal crystals and evenly disperses the trigonal hard phase in the hexagonal matrix, is a heat-resistant alloy with high breaking strength and a super heat-resistant alloy. It is ideal as a cutting tool for alloys, stainless steel, etc. In order to produce the silicon nitride sintered body for tool parts of the present invention, silicon nitride used as a starting material has a high content of trigonal α-silicon nitride, for example, α-silicon nitride.
It is desirable to use a powder with a powder content of 50% or more, and the average particle size of the powder is 2 μm or less.
In addition, if silicon nitride powder containing amorphous silicon nitride with an α rate of 50% or more is used as a starting material, sintering will be promoted due to the fine powder, but depending on the manufacturing method of silicon nitride powder, a large amount of oxygen Particular attention must be paid to the oxygen content since this oxygen content may reduce the formation of a trigonal crystal structure in the sintered body. 2 to 17% by weight of such silicon nitride powder and powder of at least one of nitrides, oxynitrides, or mutual solid solutions of B, Al, Ga, In, and Tl, which are group 3b elements of the periodic table. and 1a of the periodic table,
Group 2a and 3a elements Li, Na, K, Mg, Ca, Sr,
Ba, Sc, Y and lanthanide oxides, nitrides,
1 to 16% by weight of powder of at least one of oxynitrides or mutual solid solutions thereof is placed in a container made of stainless steel, ceramics , stainless steel cemented carbide, rubber, etc. 4 series,
The mixed powder is mixed and ground together with ZrO 2 balls, steel balls, or cemented carbide balls, and this mixed powder is packed into a sintering mold made of carbon or graphite and subjected to high-frequency pressure sintering, electric pressure sintering, and gas heating. The sintered body of the present invention is produced by sintering by hot pressing such as pressure sintering. In addition, a compact formed by molding the mixed powder in a mold, or a compact obtained by pre-sintering this compact at a temperature lower than the sintering temperature and then machining it, is normally sintered (without processing) in a non-oxidizing atmosphere including vacuum. The sintered body of the present invention is produced by sintering (including pressure sintering) or by sintering while pressurizing with atmospheric gas. Furthermore, if necessary, the sintered body can be subjected to hydrostatic pressing (HIP) treatment to promote densification of the sintered body. The sintering temperature varies depending on the sintering method or blended ingredients, but is between 1500℃ and 1900℃.
A dense sintered body with a relative density of nearly 100% can be obtained at a temperature of . When producing the silicon nitride sintered body for tool parts of the present invention, Al, Al,
It may contain small amounts of impurities such as Fe, or oxygen may be adsorbed to the surface of silicon nitride powder particles to form SiO 2. Of these, 1.2% by weight or less of SiO 2 promotes sintering and densification. It works effectively, but on the other hand, if it is too large, it reduces the formation of the trigonal structure, so it is desirable to use silicon nitride powder with the highest possible purity. In addition, impurities introduced during the manufacturing process are most often introduced during the mixing and pulverizing process of the starting raw material powder.In this pulverizing process, it is possible to prevent contamination of impurities to some extent by selecting containers and balls; By using containers and balls made of stainless steel or cemented carbide to strengthen the
Although carbides, nitrides, carbonitrides, etc. of Fe group metals and metals of groups 4a, 5a, and 6a of the periodic table may be mixed in as impurities, they should be kept at 5% by weight or less when used as cutting tools and wear-resistant tools. There is no problem as long as it is an element in group 3b of the periodic table. B. Al.
Adding small amounts of Ga, In, and Tl oxides as sintering aids is good for promoting sintering and densification, and especially adding small amounts of Al 2 O 3 is effective for increasing hardness and improving wear resistance. It is also effective. However, since either of them suppresses the trigonal crystal structure, excessive addition is not preferable. Here, the reason for limiting the numerical value of the silicon nitride sintered body for tool parts of the present invention will be described. Crystal structure modifier B, Al, Ga, In, group 3b elements of the periodic table,
If the content of Tl nitrides, oxynitrides, or at least one of these mutual solid solutions is less than 2% by weight, less than 25% of trigonal crystals will be present in the crystal structure of the sintered body, resulting in a slight decrease in hardness. This makes it difficult to cut work materials such as heat-resistant alloys, super-heat-resistant alloys, and stainless steel, which have high breaking strength, and when the amount exceeds 17% by weight, the relative The content of the crystal structure modifier was determined to be 2 to 17% by weight because the amount of silicon nitride decreases, resulting in a decrease in covalent bonding, a high coefficient of thermal expansion, and a decrease in thermal conductivity, hardness, and Young's modulus. Sintering aid Li, Na, K, Mg, Ca, Sr, Ba, Sc, Y, and at least one of lanthanoid oxides, nitrides, oxynitrides, or mutual solid solutions thereof is less than 1% by weight. If the sinterability is insufficient, the strength of the sintered body will decrease, and on the other hand, if the amount exceeds 16% by weight, the hardness of the sintered body will decrease and plastic deformation will occur when used as a cutting tool. Auxiliary agent is 1-16% by weight
It was determined that Next, the silicon nitride sintered body for tool parts of the present invention will be specifically described according to examples. Example 1 Using Si 3 N 4 (α rate 90%) with an average particle size of 1 μm and various powders with an average particle size of 1 to 3 μm, each sample was blended in the proportions shown in Table 1. The sample was mixed and ground in a hexane solvent with WC-based cemented carbide balls in a stainless steel container lined with urethane. After removing the solvent from the obtained mixed powder by evaporation,
Fill a carbon mold coated with BN powder, replace the inside of the furnace with N 2 gas, and sinter under pressure at a molding pressure of 100 to 400 Kg/cm 2 , at a temperature of 1700 to 1830°C, and for a holding time of 30 to 120 minutes. did. Various properties of the obtained sintered body are shown in Table 2, and the crystal structure and compositional components of the sintered body are shown in Table 3.
【表】【table】
【表】【table】
【表】
実施例 ２
実施例１で得た試料の内、本発明の工具部品用
窒化硅素焼結体である試料番号２、３、４、６、
７と本発明から外れた比較用焼結体である試料番
号11、12、13と市販のAl2O3−TiC系セラミツク
ス及びCBN系焼結体を刃先とする複合材料を切
削用CIS基準のRNMN43相当の丸駒チツプに
各々仕上げて下記の旋削による切削試験を行い、
その結果を第４表に示した。
旋削試験条件
被削材 Ni基耐熱合金 ワスパロイHRc42（Ni
−19.4％Cr−13.6％Co−4.4％Mo−3.1％Ti−
1.5％Al−0.6％Fe）
切削速度 150ｍ／min
切込み量 0.5mm
送り速度 0.1mm／rev
湿式切削 エマルジヨンカツト（W1−３）
切削時間 2min[Table] Example 2 Among the samples obtained in Example 1, sample numbers 2, 3, 4, 6, which are silicon nitride sintered bodies for tool parts of the present invention,
7, sample numbers 11, 12, and 13, which are comparative sintered bodies outside the present invention, and composite materials with cutting edges made of commercially available Al 2 O 3 -TiC ceramics and CBN sintered bodies according to the CIS standard for cutting. Each chip was finished into a round piece chip equivalent to RNMN43, and a cutting test was conducted using the following turning method.
The results are shown in Table 4. Turning test conditions Work material Ni-based heat-resistant alloy Waspaloy HRc42 (Ni
−19.4%Cr−13.6%Co−4.4%Mo−3.1%Ti−
1.5%Al-0.6%Fe) Cutting speed 150m/min Depth of cut 0.5mm Feed rate 0.1mm/rev Wet cutting Emulsion cut (W1-3) Cutting time 2min
【表】【table】
【表】
実施例 ３
実施例１で得た試料の内、本発明の工具部品用
窒化硅素焼結体である試料番号１、３、５、７と
本発明から外れた比較用焼結体である試料番号
11、12、13と市販のTi（CN）系サーメツト、
Al2O3−TiC系セラミツクス及びCIS基準K10相当
の超硬合金を各々CIS基準のSNP432チツプに仕
上げて下記のフライスによる断続切削試験を行
い、その結果を第５表に示した。
フライスによる断続試験条件
被削材 インコネル718 28×190角材（HRc41）
切削速度 125ｍ／min
切込み量 2.0mm
カツター送り速度 0.11mm／１刃
テープル送り速度 10mm／min
カツター MD1004R[Table] Example 3 Among the samples obtained in Example 1, sample numbers 1, 3, 5, and 7, which are silicon nitride sintered bodies for tool parts of the present invention, and comparative sintered bodies, which are different from the present invention. a certain sample number
11, 12, 13 and commercially available Ti(CN)-based cermets,
Al 2 O 3 -TiC ceramics and cemented carbide equivalent to CIS standard K10 were each finished into CIS standard SNP432 chips and subjected to interrupted cutting tests using the following milling cutter, and the results are shown in Table 5. Intermittent test conditions for milling Work material Inconel 718 28×190 square material (HRc41) Cutting speed 125m/min Depth of cut 2.0mm Cutter feed rate 0.11mm/1 blade table feed rate 10mm/min Cutter MD1004R
【表】【table】
【表】
実施例 ４
平均粒子径0.5μｍのSi3N4（α率94.5％）と平均
粒子径6μｍのSi3N4（α率79％）と平均粒子径１
〜3μｍの各種粉末を使用して第６表に示した割
合に各試料を配合し、４％のパラフインを加えた
後ヘキサン溶媒中WC基超硬合金製ボールと共に
ステンレス製容器の中で混合粉砕した。得られた
混合粉末から溶媒を蒸発除去後、金型モールドで
成形し10-2mmHg真空中で400℃30分間予備焼結を
行つてパラフインを除去した。次いで10-2mmHg
真空中で1500℃迄昇温した後N2ガスで炉内を置
換し、0.5／minのN2ガス流量中で第６表に示
す焼結温度迄昇温した。この１度焼結して相対密
度95％以上となつた試料をN2ガス雰囲気中
1000atm、1700℃、40分保持の条件でHIP処理を
行つた。得られた焼結体の諸特性を第７表に示
し、その焼結体の結晶構造及び組成成分を第８表
に示した。[Table] Example 4 Si 3 N 4 with an average particle size of 0.5 μm (α rate 94.5%), Si 3 N 4 with an average particle size of 6 μm (α rate 79%), and average particle size 1
Using various powders of ~3 μm, each sample was blended in the proportions shown in Table 6, and after adding 4% paraffin, they were mixed and pulverized in a stainless steel container with WC-based cemented carbide balls in a hexane solvent. did. After evaporating the solvent from the obtained mixed powder, it was molded using a metal mold and pre-sintered at 400°C for 30 minutes in a vacuum of 10 -2 mmHg to remove paraffin. then 10 -2 mmHg
After the temperature was raised to 1500° C. in a vacuum, the inside of the furnace was replaced with N 2 gas, and the temperature was raised to the sintering temperature shown in Table 6 at a flow rate of 0.5/min N 2 gas. This sample, which has been sintered once and has a relative density of 95% or more, is placed in an N2 gas atmosphere.
HIP treatment was performed at 1000 atm, 1700°C, and held for 40 minutes. Table 7 shows the properties of the obtained sintered body, and Table 8 shows the crystal structure and composition of the sintered body.
【表】【table】
【表】【table】
【表】【table】
【表】【table】
【表】
実施例 ５
実施例４の本発明の工具部品用窒化硅素焼結体
である試料番号14、16、17、19と実施例１の本発
明を外れた試料番号11、12、13と市販のAl2O3−
TiC系セラミツクス及びCBN系焼結体を刃先と
する複合材料を比較に加えて切削用CIS基準の
RNMN43相当の丸駒チツプに各々仕上げて下記
の旋削による切削試験を行い、その結果を第９表
に示した。
旋削試験条件
被削材 Co基耐熱合金
切削速度 100ｍ／min
切込み量 0.5mm
送り速度 エマルジヨンカツト（W1−３）
切削時間 5min[Table] Example 5 Sample numbers 14, 16, 17, and 19, which are silicon nitride sintered bodies for tool parts according to the present invention in Example 4, and sample numbers 11, 12, and 13, which are outside the present invention in Example 1. Commercially available Al 2 O 3 −
Composite materials with cutting edges made of TiC ceramics and CBN sintered bodies were compared, and CIS standards for cutting were also compared.
Each chip was finished into a round piece chip equivalent to RNMN43 and subjected to the following cutting test by turning, and the results are shown in Table 9. Turning test conditions Work material Co-based heat-resistant alloy Cutting speed 100m/min Depth of cut 0.5mm Feed rate Emulsion cut (W1-3) Cutting time 5min
【表】
実施例 ６
実施例４の本発明の工具部品用窒化硅素焼結体
である試料番号16、21、22、23と実施例１の本発
明を外れた試料番号11、12、13と市販のTi（CN）
系サーメツト、Al2O3−TiC系セラミツクス及び
CBN系焼結体を刃先とする複合材料を比較に加
えてCIS基準のTNP332に仕上げて下記のフライ
スによる断続切削試験を行い、その結果を第10表
に示した。
フライスによる切削条件
被削材 SCM3の浸炭材（HRc55）
切削速度 200ｍ／min
切込み量 0.25mm
送り速度 1.15mm／１刃[Table] Example 6 Sample numbers 16, 21, 22, and 23, which are silicon nitride sintered bodies for tool parts of the present invention in Example 4, and sample numbers 11, 12, and 13, which are not in accordance with the present invention in Example 1. Commercially available Ti(CN)
based cermets, Al 2 O 3 -TiC based ceramics, and
In addition to comparing a composite material with a cutting edge made of CBN-based sintered body, the material was finished to TNP332 according to the CIS standard, and an interrupted cutting test was conducted using the following milling cutter, and the results are shown in Table 10. Cutting conditions for milling Work material SCM3 carburized material (HRc55) Cutting speed 200m/min Depth of cut 0.25mm Feed rate 1.15mm/1 tooth
【表】
以上の実施例１〜６の結果から明らかなように
三方晶であるα−型の結晶構造からなる主硬質相
を有する本発明の工具部品用窒化硅素焼結体は、
CBN系工具材料に近い硬度を有し、高熱伝導度
及び低熱膨張の切削工具用材料となり、特に酸化
物を用いずに例えば実施例１の試料番号４のよう
なAlNとYNの窒化物を出発原料とするとAlとＹ
がSi3N4の格子中に優先的に固溶した窒素に富ん
だ三方晶の含有した焼結体となり、ヤング率の増
大、熱伝導度向上、熱膨張率が低下する傾向があ
り、このために耐熱衝撃性の大きい三方晶結晶構
造を有する窒化硅素焼結体になる。このように本
発明の窒化硅素焼結体は、切削工具として使用し
た場合被削材が耐熱合金、鋼等のように破断強度
の高い材料に対しては従来のセラミツクスの５〜
10倍の寿命を示すことから構造用材料として種々
の用途にも利用できる可能性がある産業上有用な
窒化硅素焼結体である。[Table] As is clear from the results of Examples 1 to 6 above, the silicon nitride sintered body for tool parts of the present invention has a main hard phase consisting of a trigonal α-type crystal structure.
It has a hardness close to that of CBN-based tool materials, and is a material for cutting tools with high thermal conductivity and low thermal expansion, starting from nitrides of AlN and YN, such as sample number 4 in Example 1, without using any oxides. Al and Y as raw materials
becomes a sintered body containing nitrogen-rich trigonal crystals preferentially dissolved in the Si 3 N 4 lattice, which tends to increase Young's modulus, improve thermal conductivity, and decrease coefficient of thermal expansion. Therefore, the silicon nitride sintered body has a trigonal crystal structure with high thermal shock resistance. As described above, when the silicon nitride sintered body of the present invention is used as a cutting tool, it is better than conventional ceramics for materials with high breaking strength such as heat-resistant alloys and steel.
It is an industrially useful silicon nitride sintered body that has the potential to be used in various applications as a structural material because it exhibits a lifespan 10 times longer.
Claims (1)
結体が下記(A)式で示される固溶体の三方晶結晶構
造を25〜95重量％含有していることを特徴とする
工具部品用窒化硅素焼結体。 （Sia、Mb）12（Ox、Ny）16 ……(A) 但し、Siは、硅素、ＭはAl、Ga、Li、Ｋ、
Mg、Ca、Sr、Ba、Ｂ、Sc、Ｙ及びランタノイ
ドの中の少なくとも１種の元素を表わし、Ｏは酸
素、Ｎは窒素を表わす。ａ及びｂはそれぞれSiと
Ｍのモル比を表わし、ｘ、ｙはそれぞれ酸素と窒
素のモル比を表わし、ａ＋ｂ＝１、ａ＞０、ｂ＞
０、ｘ＋ｙ＝１、ｘ≧０でなる。 ２ 上記焼結体がホウ素、アルミニウム、ガリウ
ムの窒化物、酸窒化物又はこれらの相互固溶体の
中の少なくとも１種の結晶構造調整剤２〜17重量
％とリチウム、カリウム、マグネシウム、カルシ
ウム、ストロンチウム、バリウム、スカンジウ
ム、イツトリウム及びランタノイドの酸化物、窒
化物、酸窒化物又はこれらの相互固溶体の中の少
なくとも１種の焼結助剤１〜16重量％と残り窒化
硅素と不可避不純物とを焼結したものであること
を特徴とする特許請求の範囲第１項記載の工具部
品用窒化硅素焼結体。[Scope of Claims] 1. A sintered body mainly composed of silicon nitride, characterized in that the sintered body contains 25 to 95% by weight of a trigonal crystal structure of a solid solution represented by the following formula (A). Silicon nitride sintered body for tool parts. (Sia, Mb) 12 (Ox, Ny) 16 ...(A) However, Si is silicon, M is Al, Ga, Li, K,
It represents at least one element among Mg, Ca, Sr, Ba, B, Sc, Y, and lanthanoids, O represents oxygen, and N represents nitrogen. a and b each represent the molar ratio of Si and M, x and y each represent the molar ratio of oxygen and nitrogen, a+b=1, a>0, b>
0, x+y=1, x≧0. 2 The sintered body contains 2 to 17% by weight of at least one crystal structure modifier among boron, aluminum, gallium nitrides, oxynitrides, or mutual solid solutions thereof, and lithium, potassium, magnesium, calcium, strontium, 1 to 16% by weight of a sintering aid of at least one of oxides, nitrides, oxynitrides, or mutual solid solutions of barium, scandium, yttrium, and lanthanides, and the remaining silicon nitride and unavoidable impurities are sintered. A silicon nitride sintered body for tool parts according to claim 1, which is a silicon nitride sintered body for tool parts.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58199611A JPS6090873A (en) | 1983-10-25 | 1983-10-25 | Silicon nitride sintered body for tool part |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58199611A JPS6090873A (en) | 1983-10-25 | 1983-10-25 | Silicon nitride sintered body for tool part |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6090873A JPS6090873A (en) | 1985-05-22 |
| JPH0537944B2 true JPH0537944B2 (en) | 1993-06-07 |
Family
ID=16410734
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58199611A Granted JPS6090873A (en) | 1983-10-25 | 1983-10-25 | Silicon nitride sintered body for tool part |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6090873A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015016269A1 (en) * | 2013-07-31 | 2015-02-05 | 京セラ株式会社 | Silicon nitride-based sintered body, and corrosion-resistant member, sliding member and member for paper-making machine each manufactured using same |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS569278A (en) * | 1979-07-06 | 1981-01-30 | Tokyo Shibaura Electric Co | Manufacture of heat resistant high strength sintered body |
| JPS5626772A (en) * | 1979-08-14 | 1981-03-14 | Sumitomo Electric Industries | Sintered body for superhard tool and manufacture thereof |
| JPS5874572A (en) * | 1982-07-30 | 1983-05-06 | 住友電気工業株式会社 | Plasticity working tool for copper and copper alloy |
| JPS6027655A (en) * | 1983-07-25 | 1985-02-12 | 工業技術院長 | Silicon nitride sintered body and manufacture |
-
1983
- 1983-10-25 JP JP58199611A patent/JPS6090873A/en active Granted
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015016269A1 (en) * | 2013-07-31 | 2015-02-05 | 京セラ株式会社 | Silicon nitride-based sintered body, and corrosion-resistant member, sliding member and member for paper-making machine each manufactured using same |
| JP6023337B2 (en) * | 2013-07-31 | 2016-11-09 | 京セラ株式会社 | Silicon nitride sintered body, corrosion-resistant member, sliding member and paper machine member using the same |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6090873A (en) | 1985-05-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPS6227033B2 (en) | ||
| JPS6011288A (en) | Surface coated sialon-base ceramic tool member | |
| JP3476507B2 (en) | Method for producing cubic boron nitride-containing sintered body | |
| JPS638075B2 (en) | ||
| JP2546709B2 (en) | High strength cubic boron nitride containing sintered body | |
| JP4110338B2 (en) | Cubic boron nitride sintered body | |
| JPS644988B2 (en) | ||
| JP4110339B2 (en) | Cubic boron nitride sintered body | |
| JPH0537944B2 (en) | ||
| EP0123292B1 (en) | Silicon nitride sintered body and method for preparing the same | |
| JP2000218411A (en) | Cubic boron nitride sintered body cutting tool | |
| JPS63100055A (en) | Alumina base ceramic for cutting tool and manufacture | |
| JPS6257597B2 (en) | ||
| JPH07172919A (en) | Titanium-compound sintered material | |
| JP2712737B2 (en) | Silicon nitride based sintered material with high toughness and high strength | |
| JPH07172924A (en) | Highly tough sintered compact for tool and its production | |
| JP2997334B2 (en) | Fiber reinforced ceramics | |
| JP3591799B2 (en) | High toughness silicon nitride based sintered body and method for producing the same | |
| JPS6257596B2 (en) | ||
| JPH0764639B2 (en) | Method for manufacturing silicon nitride sintered body | |
| JP3615634B2 (en) | High toughness silicon nitride sintered body and manufacturing method thereof | |
| JPS59213676A (en) | High strength silicon nitride sintered body and manufacture | |
| JPH059386B2 (en) | ||
| JPS638074B2 (en) | ||
| JPH0545549B2 (en) |