JPH04127085A - Manufacture of nuclear fuel pellet - Google Patents
Manufacture of nuclear fuel pelletInfo
- Publication number
- JPH04127085A JPH04127085A JP2249610A JP24961090A JPH04127085A JP H04127085 A JPH04127085 A JP H04127085A JP 2249610 A JP2249610 A JP 2249610A JP 24961090 A JP24961090 A JP 24961090A JP H04127085 A JPH04127085 A JP H04127085A
- Authority
- JP
- Japan
- Prior art keywords
- sintering
- metal soap
- metal
- nuclear fuel
- al2o3
- 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.)
- Granted
Links
- 239000008188 pellet Substances 0.000 title claims abstract description 30
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 25
- 239000003758 nuclear fuel Substances 0.000 title claims description 13
- 229910052751 metal Inorganic materials 0.000 claims abstract description 37
- 239000002184 metal Substances 0.000 claims abstract description 37
- 238000005245 sintering Methods 0.000 claims abstract description 32
- 239000000344 soap Substances 0.000 claims abstract description 26
- 239000000314 lubricant Substances 0.000 claims abstract description 14
- 239000000654 additive Substances 0.000 claims abstract description 13
- 238000000465 moulding Methods 0.000 claims abstract description 10
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 8
- 239000001301 oxygen Substances 0.000 claims abstract description 8
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 8
- 239000002245 particle Substances 0.000 claims description 4
- 230000006641 stabilisation Effects 0.000 claims description 2
- 238000011105 stabilization Methods 0.000 claims description 2
- 239000000843 powder Substances 0.000 abstract description 21
- 239000000446 fuel Substances 0.000 abstract description 16
- 239000000463 material Substances 0.000 abstract description 8
- WZECUPJJEIXUKY-UHFFFAOYSA-N [O-2].[O-2].[O-2].[U+6] Chemical compound [O-2].[O-2].[O-2].[U+6] WZECUPJJEIXUKY-UHFFFAOYSA-N 0.000 abstract description 6
- CEGOLXSVJUTHNZ-UHFFFAOYSA-K aluminium tristearate Chemical compound [Al+3].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O CEGOLXSVJUTHNZ-UHFFFAOYSA-K 0.000 abstract description 6
- 229940063655 aluminum stearate Drugs 0.000 abstract description 6
- HQKMJHAJHXVSDF-UHFFFAOYSA-L magnesium stearate Chemical compound [Mg+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O HQKMJHAJHXVSDF-UHFFFAOYSA-L 0.000 abstract description 6
- 229910000439 uranium oxide Inorganic materials 0.000 abstract description 6
- 150000001875 compounds Chemical class 0.000 abstract description 5
- 239000013078 crystal Substances 0.000 abstract description 5
- 150000002739 metals Chemical class 0.000 abstract description 5
- 239000011882 ultra-fine particle Substances 0.000 abstract description 4
- CJZGTCYPCWQAJB-UHFFFAOYSA-L calcium stearate Chemical compound [Ca+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O CJZGTCYPCWQAJB-UHFFFAOYSA-L 0.000 abstract description 3
- 239000008116 calcium stearate Substances 0.000 abstract description 3
- 235000013539 calcium stearate Nutrition 0.000 abstract description 3
- 235000019359 magnesium stearate Nutrition 0.000 abstract description 3
- 238000000354 decomposition reaction Methods 0.000 abstract description 2
- 239000006185 dispersion Substances 0.000 abstract description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract 3
- 229910052593 corundum Inorganic materials 0.000 abstract 3
- 229910001845 yogo sapphire Inorganic materials 0.000 abstract 3
- 238000000034 method Methods 0.000 description 8
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 7
- 239000002994 raw material Substances 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 5
- 239000003795 chemical substances by application Substances 0.000 description 5
- 239000012071 phase Substances 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- 230000000996 additive effect Effects 0.000 description 4
- 239000011575 calcium Substances 0.000 description 4
- 239000000919 ceramic Substances 0.000 description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- 238000009835 boiling Methods 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 239000011777 magnesium Substances 0.000 description 3
- XOOUIPVCVHRTMJ-UHFFFAOYSA-L zinc stearate Chemical compound [Zn+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O XOOUIPVCVHRTMJ-UHFFFAOYSA-L 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 2
- BYFGZMCJNACEKR-UHFFFAOYSA-N aluminium(i) oxide Chemical compound [Al]O[Al] BYFGZMCJNACEKR-UHFFFAOYSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 229910052791 calcium Inorganic materials 0.000 description 2
- 238000000748 compression moulding Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 2
- 239000010931 gold Substances 0.000 description 2
- 229910052737 gold Inorganic materials 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000007791 liquid phase Substances 0.000 description 2
- 238000001000 micrograph Methods 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000010298 pulverizing process Methods 0.000 description 2
- 229910001868 water Inorganic materials 0.000 description 2
- 239000011701 zinc Substances 0.000 description 2
- 229910052725 zinc Inorganic materials 0.000 description 2
- 235000021355 Stearic acid Nutrition 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 238000005056 compaction Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000005469 granulation Methods 0.000 description 1
- 230000003179 granulation Effects 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 1
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 239000008117 stearic acid Substances 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E30/00—Energy generation of nuclear origin
- Y02E30/30—Nuclear fission reactors
Landscapes
- Inorganic Compounds Of Heavy Metals (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は原子力用セラミックス燃料の製造法に関し、詳
しくは、焼結促進材あるいは結晶粒径粗大化材を燃料ベ
レットの粉末成型時の潤滑材として活用する核燃料ペレ
ットの製造法に関するものである。Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a method for producing ceramic fuel for nuclear power use, and more specifically, the present invention relates to a method for producing ceramic fuel for nuclear power use, and more particularly, a sintering accelerator or grain size coarsening agent is used as a lubricant during powder molding of fuel pellets. This article concerns a method for producing nuclear fuel pellets that can be used as fuel.
（従来の技術）
核燃料でない一般のセラミックスを粉末成型・焼結法に
より製造する場合、通常粉末成型時の摩擦力を減するた
めに、ステアリン酸等の有機化合物やステアリン酸亜鉛
をはじめとする金属石けんよりなる潤滑材が使用されて
いるが、同様な粉末成型・焼結法によって核燃料ペレッ
トを製造する場合は、ペレット中の不純物の制限から金
属石けん類では現在のところステアリン酸亜鉛が用いら
れているのみである。これはステアリン酸亜鉛が焼結過
程において、金属亜鉛と水、炭酸ガスに分割すると共に
、亜鉛が低沸点金属（沸点９０７℃）であるため、通常
の焼結温度１６００℃〜１７５０℃では蒸発してしまい
ペレット中に残存しないことによるものである。(Prior technology) When manufacturing general ceramics that are not nuclear fuels by powder molding and sintering, organic compounds such as stearic acid and metals such as zinc stearate are usually used to reduce the frictional force during powder molding. A lubricant made of soap is currently used, but when producing nuclear fuel pellets using the same powder molding and sintering method, zinc stearate is currently used in metal soaps due to restrictions on impurities in the pellets. There is only one. This is because zinc stearate splits into metallic zinc, water, and carbon dioxide during the sintering process, and since zinc is a low boiling point metal (boiling point 907°C), it does not evaporate at the normal sintering temperature of 1600°C to 1750°C. This is due to the fact that it does not remain in the pellet.
ところで最近の研究において、Ａ １ ｔＯｘ＋ Ｃａ
ｂ、 Ｍｇｏが燃料ペレットの添加材として注目されて
いるが、これらのものはある一定収上の酸素の存在下で
は雰囲気の大部分が水素等の還元ガス条件の焼結であっ
ても、焼結を促進する焼結促進材として作用し、かつ結
晶粒径を粗大化できてＦＰ保持性を向上させることが判
ってきた。このためセラミックス核燃料ペレットの製造
に際しては、積極的にこのＡ ｌ ２０３１ ＣａＯ＋
ＭｇＯを原料粉中に添加する動きがあり、この場合、
従来ではより均質に原料粉中に混入するために、上記Ａ
１２０３等の添加材の超微粉化あるいは化合物の水溶
液分散法等がとられている。By the way, in recent research, A 1 tOx+ Ca
b. Mgo is attracting attention as an additive material for fuel pellets, but these materials cannot be sintered in the presence of oxygen at a certain yield even if the atmosphere is mostly a reducing gas such as hydrogen. It has been found that it acts as a sintering accelerator that promotes sintering, and that it can coarsen the crystal grain size and improve FP retention. For this reason, when manufacturing ceramic nuclear fuel pellets, we actively use this Al 2031 CaO+
There is a movement to add MgO to raw material powder, and in this case,
Conventionally, in order to mix more homogeneously into the raw material powder, the above A
Ultra-fine powdering of additives such as 1203 or dispersion of compounds in aqueous solutions have been adopted.
（発明が解決しようとする課Ｂ）
ところが、上記Ａ ｆ ２０．等の添加材を超微粉化す
るにはコストが高くなる問題があり、また化合物の水溶
液分散法においては取扱いに手間を要し、かつ乾燥が必
要であるとの問題を有している。(Problem B to be solved by the invention) However, the above A f 20. There is a problem in that the process of ultrafinely pulverizing additives such as compounds increases the cost, and the method of dispersing compounds in aqueous solutions requires time and effort in handling and requires drying.
本発明は畝上の如き実情に対処し、上記添加材を金属石
けんの形態にすることを見出すことにより、潤滑材とし
ての働きを与え上記酸化物の如き焼結促進材あるいは結
晶粒径粗大化材の原料粉中への均質分散、及び燃料ペレ
ット製造工程の簡略化を目的とするものである。The present invention deals with the actual situation such as ridges, and by finding that the above-mentioned additive is in the form of a metal soap, it acts as a lubricant and is used as a sintering accelerator such as the above-mentioned oxide, or as a grain coarsening agent. The purpose is to homogeneously disperse the fuel into the raw material powder and to simplify the fuel pellet manufacturing process.
（課題を解決するための手段）
即ち、上記目的に適合する本発明核燃料ペレットの製造
法の特徴は、上記ＡｌｚＯｆｆ、 ＣａＯ，ＭｇＯ、又
はこれら酸化物に変化しうる各金属を単独又は他の物質
と組み合わせて酸化ウラン粉末に添加せしめて成型し、
のち焼結せしめる核燃料ペレットの製造法において、上
記へβ２０１等の添加材を金属石けんの形態となし、成
型時の潤滑材の全部又は一部として用いることにある。(Means for Solving the Problems) That is, the feature of the method for producing nuclear fuel pellets of the present invention that satisfies the above-mentioned purpose is that the above-mentioned AlzOff, CaO, MgO, or each metal that can be converted into an oxide thereof is used alone or in combination with other substances. Combined with uranium oxide powder and molded,
In a method for producing nuclear fuel pellets that are later sintered, additives such as β201 are made into a metal soap and used as all or part of a lubricant during molding.
また請求項２記載の発明は上記製造法において雰囲気中
の酸素の量を調整することにより、まず上記金属石けん
の金属相を現出させ焼結促進を行った後、高温での該金
属石けんの安定化及び本来の粒径粗大化機能をもたらす
べく酸化物相を形成させることを特徴として、上記金属
石けんを焼結促進材として効率適に利用する上でより好
適である。In addition, the invention as claimed in claim 2 is such that in the above manufacturing method, by adjusting the amount of oxygen in the atmosphere, the metallic phase of the metallic soap is first exposed and sintering is promoted, and then the metallic soap is heated at a high temperature. It is characterized by forming an oxide phase to provide stabilization and the original particle size coarsening function, and is more suitable for efficiently utilizing the metal soap as a sintering accelerator.
以下、更に上記本発明製造法の詳細について説明すると
、先ず、本発明による核燃料ペレットの製造法は基本的
に酸化ウラン粉末にＡ １２０３． ＣａＯＭｇＯ、又
はこれら酸化物に変化しうるＡ１．Ｃａ、Ｍｇ各金金属
原理的な焼結促進材あるいは結晶粒径粗大化材として単
独あるいは２者以上組み合わせ、もしくは他の物質と組
み合わせて焼結促進材又は結晶粒粗大化材として添加し
、成型、焼結する方法である。The details of the manufacturing method of the present invention will be explained below. First, the method of manufacturing nuclear fuel pellets of the present invention basically involves adding A1203. A1. which can be converted into CaOMgO or these oxides. Ca, Mg can be added as a sintering accelerator or crystal grain coarsening agent in principle to each gold metal, either alone or in combination of two or more, or in combination with other substances as a sintering accelerator or crystal grain coarsening agent, and molded , is a method of sintering.
この場合、成型は従来既知の種々の成型法が使用可能で
あるが、最初、所要の造粒圧で圧縮し、次いで造粒され
た細粒を粉砕、篩別後、当初圧力の２０〜６０％程度の
圧力で圧縮成型し、のち焼結する２段圧縮成型法を適用
することもできる。In this case, various conventionally known molding methods can be used for molding, but first, the granulated fine particles are compressed at the required granulation pressure, then the granulated fine particles are crushed and sieved, and then the initial pressure is 20-60%. It is also possible to apply a two-stage compression molding method in which compression molding is performed at a pressure of about 100% and then sintered.
また焼結は還元雰囲気中で順次昇温し、１６００〜１８
００℃で所要時間、通常、３時間以上、加熱保持するこ
とによって行われる。In addition, sintering is performed by sequentially increasing the temperature in a reducing atmosphere to 1,600 to 18
This is carried out by heating and holding at 00° C. for a required period of time, usually 3 hours or more.
この場合、水素雰囲気中に水蒸気（８２０）を添加する
と
２ＨｚＯ＝Ｑ□＋ ２Ｈｚ
の平衡状態が形成され、酸素の存在が許されるので０□
供給のため昇温時に水蒸気を添加することが好ましい。In this case, when water vapor (820) is added to the hydrogen atmosphere, an equilibrium state of 2HzO=Q□+2Hz is formed, and since the presence of oxygen is allowed, 0□
It is preferable to add water vapor at the time of heating for feeding purposes.
しかして本発明は上記の如き基本的な製造法において特
に前記添加されるＡ ｌ ２０３． Ｃａｂ、 ＭｇＯ
を通常の形態でなく金属石けんの形態で添加材として用
いることであり、これによって該添加材に潤滑材として
の働きをも与えている。Therefore, the present invention particularly provides the above-mentioned added Al 203. Cab, MgO
is used as an additive in the form of a metal soap rather than in its usual form, thereby giving the additive a function as a lubricant.
ここで上記金属石けんの具体的形態例としてはステアリ
ン酸アルミ、ステアリン酸カルシウム、ステアリン酸マ
グネシウムであり、これら八β２０３（八１ ） 、
ＣａＯ（Ｃａ） 、 ＭｇＯ（Ｍｇ）の各金属石けんの
形態例及びその特性は下記第１表に示す如（である。Here, specific examples of the above-mentioned metal soap include aluminum stearate, calcium stearate, and magnesium stearate, and these 8β203 (81),
Examples of the forms of each metal soap, CaO (Ca) and MgO (Mg), and their characteristics are as shown in Table 1 below.
第 １ 表
上記金属石けん類の分解温度は何れも２００〜６００℃
であり、酸素の存在によって焼結助材（焼結促進材）あ
るいは結晶粒径粗大化材となるＡ １２０：ｌＣａＯ，
ＭｇＯの各酸化物と、Ｃｏ、 、 Ｈ２Ｏ等に変化する
が、この際、各化合物中の金属の割合は極めて少ないた
め残された酸化物はおのづと超微粒となって酸化ウラン
粉末に均質に混入される。Table 1 The decomposition temperature of the above metal soaps is 200 to 600℃.
120:lCaO, which becomes a sintering aid (sintering accelerator) or grain size coarsening material in the presence of oxygen.
Each oxide of MgO changes into Co, , H2O, etc. At this time, since the proportion of metal in each compound is extremely small, the remaining oxide naturally becomes ultra-fine particles and becomes homogeneous into uranium oxide powder. mixed into the
つまり、始めは潤滑材として、その後、焼結昇温時には
０□の存在が条件であるが焼結助材に転化することにな
る。That is, it is initially used as a lubricant, and then, when the temperature is increased during sintering, it is converted into a sintering aid, provided that 0□ exists.
更に、焼結助材の働きと重なるが、酸素の添加時期を金
属融点〜沸点とし、添加量を調整することにより、金属
石けんが上記酸化物になる前にＵ０２粉末粒界に金属の
薄い膜を形成し、いわゆる液相焼結となって焼結がより
促進されることが期待される。Furthermore, although this overlaps with the function of the sintering aid, by adjusting the timing of oxygen addition from the metal melting point to the boiling point and adjusting the amount added, a thin film of metal is created at the grain boundaries of the U02 powder before the metal soap becomes the above-mentioned oxide. It is expected that this will lead to so-called liquid phase sintering, which will further promote sintering.
（作用）
しかして、Ａ ｌ ２０．等の添加材を上記の如き金属
石けんの形態として原料粉酸化ウランに添加したときは
、先ず、金属石けんの形態が前記したように潤滑材の働
きをし、従来のように別途の潤滑材の添加を必要とせず
、燃料ペレットの製造工程は簡略化される。(Effect) Therefore, Al 20. When such additives are added to the raw material powder uranium oxide in the form of metal soap as described above, first, the form of metal soap acts as a lubricant as described above, and as in the case of a separate lubricant as in the past. No additives are required, simplifying the fuel pellet manufacturing process.
また、最近燃料ペレットに、焼結促進材や潤滑材密度を
減じるボア源としての有機物を加えること、即ち潤滑性
能を有しない上記金属を含む有機物を微粉化を目的とし
て潤滑材に加えて添加すること、つまり２種以上の添加
物を用いることはペレットの密度上昇の観点からはあま
り望ましくなく、この点においても本発明は、初期には
潤滑材として、その後は焼結促進材等として作用するよ
うな一材で二材を兼ねる物質を添加するものであるので
、この観点からも大きな改善となっている。In addition, recently, organic substances have been added to fuel pellets as sintering accelerators and bore sources that reduce the lubricant density, that is, organic substances containing the above metals that do not have lubricating properties are added in addition to lubricants for the purpose of pulverization. In other words, the use of two or more types of additives is not very desirable from the viewpoint of increasing the density of the pellets, and in this respect as well, the present invention works as a lubricant initially and then as a sintering accelerator etc. This is a great improvement from this point of view as well, as it adds a substance that functions as two materials in one material.
（実施例） 以下、更に本発明の具体的な実施例につき説明する。(Example) Hereinafter, further specific examples of the present invention will be described.
通常の原子炉用燃料ペレット製造に用いられる原料粉Ｕ
Ｏ□粉末に、ステアリン酸アルミ約０．４重量％を添加
し、直径Ｌｏｔｓ、高さ１０鶴の円柱状に成型し、密度
５．６ｇ／ａｄの成型体を得た。Raw material powder U used in the production of fuel pellets for normal nuclear reactors
Approximately 0.4% by weight of aluminum stearate was added to the O□ powder and molded into a cylinder with a diameter of Lots and a height of 10 cranes to obtain a molded body with a density of 5.6 g/ad.
この成型体を水素・窒素・混合気中にて２５０℃／Ｈｒ
で昇温し、９００°Ｃにて１時間保持した後、体積率０
．１％の水蒸気を前記混合ガス中に投入しながら２５０
℃／Ｈｒで１７００℃まで昇温し、更に同温度にて４時
間保持を行った後、２００℃／Ｈｒで室温まで降温した
。This molded body was heated at 250°C/Hr in a hydrogen/nitrogen mixture.
After raising the temperature at 900°C for 1 hour, the volume ratio was 0.
．． While adding 1% water vapor into the mixed gas,
The temperature was raised to 1700° C. at a rate of 1,700° C./Hr, maintained at the same temperature for 4 hours, and then lowered to room temperature at a rate of 200° C./Hr.
なお、水蒸気投入は１０００℃で停止した。Note that the water vapor injection was stopped at 1000°C.
かくして得られた燃料ペレットは健全であり、密度は９
５．８％ＴＤ、またペレット中のＡ１はＡＡ２０３換算
で約３４０ｐｐｎ＋であった。The fuel pellets thus obtained are sound and have a density of 9
TD was 5.8%, and A1 in the pellet was approximately 340 ppn+ in terms of AA203.
そして、上記ペレットの金相は第１図に示すとおりであ
り、粒径は約４０ｕｍであった。これは従来の超微粒Ａ
１２０３を約３００ｐｐｍ添加する製法により得られ
たペレット（第２図に示す）の粒径と同等である。The gold phase of the pellets was as shown in FIG. 1, and the particle size was about 40 um. This is the conventional ultrafine particle A
The particle size is equivalent to that of pellets (shown in FIG. 2) obtained by a manufacturing method in which about 300 ppm of 1203 is added.
なお、引続き上記ステアリン酸アルミの代わりにステア
リン酸カルシウム及びステアリン酸マグネシウムを添加
して、同じように実験を行ったところ、何れにしてもス
テアリン酸アルミと同等の燃料ペレットを得ることがで
きた。Incidentally, when the same experiment was carried out by adding calcium stearate and magnesium stearate instead of the above-mentioned aluminum stearate, fuel pellets equivalent to those of aluminum stearate could be obtained in either case.
（発明の効果）
以上説明したように、本発明核燃料ペレットの製造法は
、Ａ １２０． 、ＣａＯ，ＭｇＯ，Ａ ｌ 、Ｃａ、
Ｍｇを金属石けんの形態として酸化ウランに添加して成
型し、のち焼結せしめるものであり、特に上記酸化金属
又は金属を金属石けんの形態として用いることにより、
これら金属類が最初は粉末成型時の潤滑材として、そし
て焼結時には焼結促進材及び結晶粒径粗大化材としては
たらくことができ、従来要した潤滑材と焼結促進材の２
種混合の必要をなくし燃料ペレット製造の混合工程を簡
略化することができた。(Effects of the Invention) As explained above, the method for producing nuclear fuel pellets of the present invention is based on A120. , CaO, MgO, Al, Ca,
Mg is added to uranium oxide in the form of a metal soap, molded, and then sintered. In particular, by using the above metal oxide or metal in the form of a metal soap,
These metals can initially function as lubricants during powder compaction, and then as sintering accelerators and crystal grain size coarsening agents during sintering.
This eliminates the need for seed mixing and simplifies the mixing process for producing fuel pellets.
そして、上記金属石けんが焼結促進材に変化する際には
、該金属石けんに含まれる前記Ａｆ等の金属が微量であ
ることから、残される酸化物（へ１２０３等）はおのず
と超微粒となってＵＯ，原料粉に均質に混入され、その
結果、従来要した高価な超微粒酸化物を使用する必要が
なくなり、コストダウンを図ることが可能となった。When the metal soap changes into a sintering accelerator, the remaining oxides (He1203, etc.) naturally become ultra-fine particles because the metal soap contains a trace amount of metals such as Af. UO is homogeneously mixed into the raw material powder, and as a result, it is no longer necessary to use the expensive ultrafine oxide that was conventionally required, making it possible to reduce costs.
更に、前記本発明製造法において、雰囲気中の酸素の量
を調整することにより、上記まず金属石けんの金属相を
現出させて液相焼結を行い、のち酸化物相を形成させ、
強固な焼結とペレットの粗粒化を同時に行いうる等、本
発明製造法の実用上の価値には極めて大きいものがある
。Furthermore, in the production method of the present invention, by adjusting the amount of oxygen in the atmosphere, the metal phase of the metal soap is first revealed and liquid phase sintering is performed, and then an oxide phase is formed.
The production method of the present invention has extremely great practical value, such as the ability to perform strong sintering and grain coarsening of pellets at the same time.
第１図はＵＯ□粉末にステアリン酸アルミを約０゜４重
量％添加し成型後焼結して得られた本発明製法による燃
料ペレットを１５０倍の倍率で撮影した金属組織顕微鏡
写真、第２図はＵＯ，粉末にＡｌ２Ｏ、の超微粒粉末を
約３００ｐｐｎ＋添加し成型後焼結して得られた従来製
法による燃料ペレットを１５０倍の倍率で撮影した金属
組織顕微鏡写真である。
特許出願人 原子燃料工業株式会社代理人 弁理士
宮 本 泰
第２１／１Figure 1 is a metallographic micrograph taken at 150x magnification of a fuel pellet obtained by the manufacturing method of the present invention obtained by adding approximately 0°4% by weight of aluminum stearate to UO□ powder, molding, and sintering. The figure is a metallographic micrograph taken at 150x magnification of a fuel pellet obtained by a conventional manufacturing method, in which approximately 300 ppn+ of ultrafine powder of Al2O was added to the UO powder, molded, and then sintered. Patent applicant Yasushi Miyamoto No. 21/1, Attorney for Nuclear Fuel Industry Co., Ltd.
Claims (1)
物に変化しうる各金属を単独又は他の物質と組み合わせ
て酸化ウラン粉末に添加せしめて成型し、のち焼結せし
める核燃料ペレットの製造法において、上記Ａｌ＿２Ｏ
＿３等の添加材を金属石けんの形態となし、成型時の潤
滑材の全部又は一部として用いることを特徴とする核燃
料ペレットの製造法。２、請求項１に記載の製造法にお
いて、雰囲気中の酸素の量を調整することにより、まず
上記金属石けんの金属相を現出させ焼結促進を行った後
、高温での該金属石けんの安定化及び本来の粒径粗大化
機能をもたらすべく酸化物相を形成させることを特徴と
する核燃料ペレットの製造法。1. In a method for producing nuclear fuel pellets, the above-mentioned Al_2O
A method for producing nuclear fuel pellets, characterized in that additives such as _3 are in the form of metal soap and used as all or part of a lubricant during molding. 2. In the manufacturing method according to claim 1, by adjusting the amount of oxygen in the atmosphere, the metal phase of the metal soap is first exposed and sintering is promoted, and then the metal soap is heated at a high temperature. A method for producing nuclear fuel pellets, characterized by forming an oxide phase to provide stabilization and inherent particle size coarsening functions.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2249610A JPH0833470B2 (en) | 1990-09-18 | 1990-09-18 | Manufacturing method of nuclear fuel pellets |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2249610A JPH0833470B2 (en) | 1990-09-18 | 1990-09-18 | Manufacturing method of nuclear fuel pellets |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04127085A true JPH04127085A (en) | 1992-04-28 |
| JPH0833470B2 JPH0833470B2 (en) | 1996-03-29 |
Family
ID=17195591
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2249610A Expired - Fee Related JPH0833470B2 (en) | 1990-09-18 | 1990-09-18 | Manufacturing method of nuclear fuel pellets |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0833470B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012088317A (en) * | 2010-10-20 | 2012-05-10 | Korea Atomic Energy Research Inst | Solid solution concentration adjustment method for crystal grain boundary and periphery of crystal grain boundary of heterogeneous additive element, and method of manufacturing nuclear fuel sintered body having large crystal grain using the same |
| RU2630898C1 (en) * | 2015-10-20 | 2017-09-14 | Акционерное общество "Ульбинский металлургический завод" | Method of manufacturing nuclear fuel tablets using alloying |
| RU2651799C1 (en) * | 2017-08-09 | 2018-04-27 | Федеральное государственное унитарное предприятие "Научно-исследовательский технологический институт имени А.П. Александрова" | Nuclear fuel manufacturing method |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01248092A (en) * | 1988-03-29 | 1989-10-03 | Mitsubishi Nuclear Fuel Co Ltd | Manufacture of nuclear fuel pellet |
-
1990
- 1990-09-18 JP JP2249610A patent/JPH0833470B2/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01248092A (en) * | 1988-03-29 | 1989-10-03 | Mitsubishi Nuclear Fuel Co Ltd | Manufacture of nuclear fuel pellet |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012088317A (en) * | 2010-10-20 | 2012-05-10 | Korea Atomic Energy Research Inst | Solid solution concentration adjustment method for crystal grain boundary and periphery of crystal grain boundary of heterogeneous additive element, and method of manufacturing nuclear fuel sintered body having large crystal grain using the same |
| US9190179B2 (en) | 2010-10-20 | 2015-11-17 | Korea Atomic Energy Research Institute | Method of controlling solubility of additives at and near grain boundaries, and method of manufacturing sintered nuclear fuel pellet having large grain size using the same |
| RU2630898C1 (en) * | 2015-10-20 | 2017-09-14 | Акционерное общество "Ульбинский металлургический завод" | Method of manufacturing nuclear fuel tablets using alloying |
| RU2651799C1 (en) * | 2017-08-09 | 2018-04-27 | Федеральное государственное унитарное предприятие "Научно-исследовательский технологический институт имени А.П. Александрова" | Nuclear fuel manufacturing method |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0833470B2 (en) | 1996-03-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| ES2951821T3 (en) | Aluminum-based nanogalvanic compositions useful for the generation of hydrogen gas and corresponding low-temperature processing | |
| US7820138B2 (en) | Indium oxide powder and method for producing same | |
| JP2010132467A (en) | Method for producing oxide | |
| JPH04127085A (en) | Manufacture of nuclear fuel pellet | |
| US3161949A (en) | Refractory metal base alloys and method of making same | |
| US4115113A (en) | Process for the preparation of molybdenum based alloys by sintering | |
| US3275564A (en) | Process of fabrication of sintered compounds based on uranium and plutonium | |
| US2810182A (en) | Ceramic moulding process | |
| KR100235522B1 (en) | Direct nitridation process of metal having a low melting point | |
| JP6648161B2 (en) | Zirconium boride and method for producing the same | |
| US2952535A (en) | Sintering metal oxides | |
| US4108650A (en) | Process for the preparation of molybdenum based alloys with solid reinforcing elements by sintering | |
| KR102016916B1 (en) | Method for producing LLZO oxide solid electrolyte powder | |
| US3025137A (en) | Production of sintered compacts of beryllia | |
| JPH05161848A (en) | Preparation of high-activity and high-strength nickel/ magnesia catalyst | |
| US3066022A (en) | Process for the manufacture of pulverized iron | |
| US3327027A (en) | Process for the production of plutonium oxide-containing nuclear fuel powders | |
| KR20150071728A (en) | Fe Powders of Heat source in Thermal Batteries and Method for Fabricating thereof | |
| JP3091555B2 (en) | Manufacturing method of nuclear fuel assembly | |
| JP2505119B2 (en) | Manufacturing method of nuclear fuel pellets | |
| US3652746A (en) | Process for producing metal powder containing iron and molybdenum | |
| JPH10251714A (en) | Production of silver powder for powder metallurgy | |
| Modl-Onitsch | Observations on the Sintering of SAP | |
| JPH10332861A (en) | Method for preparing uranium mononitride | |
| JPS5930775B2 (en) | Pre-treatment method for sintering raw materials |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| LAPS | Cancellation because of no payment of annual fees |