JP2745889B2 - Method of manufacturing high-strength steel member by injection molding method - Google Patents
Method of manufacturing high-strength steel member by injection molding methodInfo
- Publication number
- JP2745889B2 JP2745889B2 JP3224552A JP22455291A JP2745889B2 JP 2745889 B2 JP2745889 B2 JP 2745889B2 JP 3224552 A JP3224552 A JP 3224552A JP 22455291 A JP22455291 A JP 22455291A JP 2745889 B2 JP2745889 B2 JP 2745889B2
- Authority
- JP
- Japan
- Prior art keywords
- weight
- powder
- injection molding
- strength steel
- raw material
- 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
- 229910000831 Steel Inorganic materials 0.000 title claims description 14
- 239000010959 steel Substances 0.000 title claims description 14
- 238000001746 injection moulding Methods 0.000 title claims description 8
- 238000004519 manufacturing process Methods 0.000 title claims description 5
- 239000011230 binding agent Substances 0.000 claims description 15
- 239000002994 raw material Substances 0.000 claims description 15
- 239000000843 powder Substances 0.000 claims description 14
- 239000000203 mixture Substances 0.000 claims description 12
- 239000002245 particle Substances 0.000 claims description 12
- 239000000956 alloy Substances 0.000 claims description 10
- 229910045601 alloy Inorganic materials 0.000 claims description 10
- 238000000034 method Methods 0.000 claims description 8
- 239000000463 material Substances 0.000 claims description 6
- 239000002184 metal Substances 0.000 claims description 6
- 229910052751 metal Inorganic materials 0.000 claims description 6
- 229910021382 natural graphite Inorganic materials 0.000 claims description 6
- 238000005245 sintering Methods 0.000 claims description 6
- 238000004898 kneading Methods 0.000 claims description 5
- 239000012535 impurity Substances 0.000 claims description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 3
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 3
- 239000004698 Polyethylene Substances 0.000 claims description 2
- 235000021355 Stearic acid Nutrition 0.000 claims description 2
- 239000012298 atmosphere Substances 0.000 claims description 2
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 claims description 2
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 claims description 2
- 239000012188 paraffin wax Substances 0.000 claims description 2
- -1 polyethylene Polymers 0.000 claims description 2
- 229920000573 polyethylene Polymers 0.000 claims description 2
- 239000008117 stearic acid Substances 0.000 claims description 2
- 239000000047 product Substances 0.000 description 12
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 8
- 229910018106 Ni—C Inorganic materials 0.000 description 5
- 238000002347 injection Methods 0.000 description 3
- 239000007924 injection Substances 0.000 description 3
- 238000009864 tensile test Methods 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000012778 molding material Substances 0.000 description 2
- 238000005303 weighing Methods 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 239000011265 semifinished product Substances 0.000 description 1
- 238000009692 water atomization Methods 0.000 description 1
Landscapes
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
- Powder Metallurgy (AREA)
Description
【0001】[0001]
【産業上の利用分野】本発明は、OA機器、精密機器、
自動車部品等に利用される高強度鋼部材の改良並びにそ
の製造法に関する。The present invention relates to OA equipment, precision equipment,
The present invention relates to an improvement of a high-strength steel member used for an automobile part and the like and a method of manufacturing the same.
【0002】[0002]
【従来の技術】OA機器、精密機器、自動車部品等に利
用される鋼部材は3次元的に複雑な形状を有するものが
多く、品質の安定と量産とを併せて確保する目的から、
近年、射出成形法による高強度鋼部材の供給が為されて
いる。2. Description of the Related Art Many steel members used for OA equipment, precision equipment, automobile parts and the like have a three-dimensionally complicated shape. For the purpose of ensuring stable quality and mass production,
In recent years, high-strength steel members have been supplied by injection molding.
【0003】しかしながら、この場合、市販されている
粉末冶金用の原料粉末の種類が限定されて居るばかり
か、射出成形法に適する原料粉末となるとさらに入手が
厳しい事もあって、強度の高い事が要求される部品に対
してはFe−Ni−C合金の利用が限度とされている。However, in this case, the types of raw material powders for powder metallurgy that are commercially available are not only limited, but also when the raw material powders suitable for the injection molding method are more difficult to obtain, high strength is required. The use of Fe-Ni-C alloys is limited for parts requiring the above.
【0004】[0004]
【本発明が解決しようとする課題】射出成形法により製
造されたFe−Ni−C合金は、焼結処理が終了した時
点に於ける引張破断強度が50Kg/mm2 前後にしか
ならない為、形状をより小さくして部品取り付けの為の
容積を狭くする事が強く要求される現代にあっては,こ
の課題を解決しようとした場合には、より強度の高い部
品を入手する事が課題として与えられていた。The Fe-Ni-C alloy produced by the injection molding method has a tensile strength at the end of the sintering process of only about 50 kg / mm 2 , so that the In today's world where there is a strong demand for smaller components and smaller volumes for mounting components, obtaining a stronger component is a challenge when solving this problem. Had been.
【0005】本発明は、上記の経過から、現行のFe−
Ni−C合金と比較して、製品の伸び率をさほど低減す
る事なく、その引張破断強度を向上させた射出成形法に
よる高強度鋼部材の供給を可能にする事を目的とする。[0005] The present invention has been developed based on the above-described process.
An object of the present invention is to enable the supply of high-strength steel members by an injection molding method in which the tensile elongation at break is improved without significantly reducing the elongation percentage of a product as compared with a Ni-C alloy.
【0006】[0006]
【課題を解決するための手段】本発明の高強度鋼部材
は、Cuの組成原料として超高圧水アトマイズ法で製造
された平均粒径が20ミクロン以下であるCu粉と、F
eとCの組成原料として平均粒径が10ミクロン以下で
あるカーボニルFe粉とを、1〜10重量%のCuと、
0.3〜1.0重量%のCと、残部が不可避的不純物を
含んだFeとの合金組成で、配合した混合粉から射出成
形した成形体の焼結体であることを特徴とするものであ
る。SUMMARY OF THE INVENTION A high-strength steel member according to the present invention comprises a Cu powder having an average particle diameter of not more than 20 microns produced by an ultra-high pressure water atomizing method as a Cu composition raw material;
a carbonyl Fe powder having an average particle size of 10 microns or less as a composition raw material of e and C, 1 to 10% by weight of Cu,
An alloy composition of 0.3 to 1.0% by weight of C and the balance of Fe containing unavoidable impurities, characterized in that it is a sintered body of a molded article injection-molded from a blended powder mixture. It is.
【0007】次に、本発明の高強度鋼部材の製造法は、
平均粒径が10ミクロン以下であるカーボニルFe粉
と、平均粒径が20ミクロン以下であるCu粉と、天然
黒鉛粉とを調合して1〜10重量%のCuと、0.3〜
1.0重量%のCと、残部が不可避的不純物を含んだF
eとからなる合金組成の金属原料粉を得ること、この金
属原料粉91.8重量%〜92.2重量%に対し有機バ
インダー7.8〜8.2重量%を加えて混練機により混
練すること、この混練物を予め用意した型に射出成形し
て得た成形体を300℃までの不活性雰囲気中で加熱す
ることによって成形体より有機バインダーを除去するこ
と、その後この脱バインダー成形体を真空焼結炉中で焼
結処理することを特徴とする。Next, the method for producing a high-strength steel member of the present invention is as follows.
A carbonyl Fe powder having an average particle size of 10 μm or less, a Cu powder having an average particle size of 20 μm or less, a natural graphite powder, and 1 to 10% by weight of Cu;
1.0% by weight of C and the balance of F containing unavoidable impurities
e) to obtain a metal raw material powder having an alloy composition consisting of 91.8% by weight to 92.2% by weight of the metal raw material powder and 7.8 to 8.2% by weight of an organic binder and kneading by a kneading machine. That is, removing the organic binder from the molded article by heating the molded article obtained by injection molding the kneaded material into a previously prepared mold in an inert atmosphere up to 300 ° C. The sintering process is performed in a vacuum sintering furnace.
【0008】[0008]
【作用】本発明にあって、高強度鋼にCuを添加したの
は、焼結体の素地であるFe相を強化する為であり、C
は高強度鋼の焼結性を向上させる為に用いたものであ
る。この場合、Cuの配合量を1〜10重量%と規定し
たのは、Cuの配合量が1重量%未満では高強度鋼の強
度が充分でなく、逆に、Cuの配合量が10重量%を超
えると、製品の材料伸びが著しく低下してしまうからで
ある。そして本発明の組成範囲のCu、C及びFeにお
いて従来のFe-Ni-C合金に比較して伸び率をさほど低
下することなく引張破断強度を向上することが出来る。In the present invention, the reason why Cu is added to the high-strength steel is to strengthen the Fe phase which is the base material of the sintered body.
Is used to improve the sinterability of high strength steel. In this case, the content of Cu is defined as 1 to 10% by weight because the strength of the high-strength steel is not sufficient when the content of Cu is less than 1% by weight, and conversely, the content of Cu is 10% by weight. This is because, if it exceeds 300, the material elongation of the product is significantly reduced. And, in the Cu, C and Fe of the composition range of the present invention, the tensile strength at break can be improved without much lowering the elongation as compared with the conventional Fe-Ni-C alloy.
【0009】また、Cの配合量を0.3〜1.0重量%
と規定したのは、Cの配合量が0.3重量%未満では高
強度鋼の強度が充分でなく、逆に、Cの配合量が1.0
重量%を超えると、製品の材料伸びが著しく低下してし
まうからである。Further, the compounding amount of C is 0.3 to 1.0% by weight.
When the amount of C is less than 0.3% by weight, the strength of the high-strength steel is not sufficient.
If the content is more than the weight%, the material elongation of the product is significantly reduced.
【0010】[0010]
【0011】上記方法に於いて,バインダ−の配合量を
7.8〜8.2重量%に限定したのは,バインダ−の配
合量が7.8重量%未満では原料を射出成型する場合の
原料の流動性が不足してまい,製品の成型性を低下させ
ことが多くなるためであり,逆に,バインダ−の配合量
が8.2重量%をこえると,脱バインダ−処理を施した
後の製品表面に発泡部や亀裂などの欠陥が発生し易くな
るためである。In the above method, the amount of the binder is limited to 7.8 to 8.2% by weight because the amount of the binder is less than 7.8% by weight when the raw material is injection-molded. This is because the fluidity of the raw materials is insufficient and the moldability of the product is often reduced. Conversely, when the blending amount of the binder exceeds 8.2% by weight, the binder is removed. This is because defects such as a foamed portion and a crack are likely to be generated on the surface of the subsequent product.
【0012】また,脱バインダ−処理温度を300度迄
としたのは,300度を,超えた脱バインダ−処理を実
施するとバインダ−がぬけ過ぎてしまいその取扱い強度
が低くなつてくることから,脱バインダ−半製品の取扱
いとして,脱バインダ−処理品を次工程へ搬送する際の
取扱い不良率が高くなつてしまうからである。Further, the reason why the binder removal processing temperature is set to 300 ° C. is that if the binder removal processing is performed at a temperature exceeding 300 ° C., the binder is excessively removed and the handling strength is reduced. This is because, as handling of the binder-free semi-finished product, the defective handling rate when the binder-free processed product is transported to the next step is increased.
【0013】C原料としてカ−ボニル鉄以外には天然黒
鉛が望ましい。それは天然黒鉛が鱗片状であることと,
本質的に高温でガス化して後に製品に浸炭拡散し,爾
後,その組成となることにあるためで,ここより不純物
の少ない天然黒鉛であることを要するも,粒径に関して
は限定する必要はない。[0013] In addition to carbonyl iron, natural graphite is preferred as the C raw material. It is that natural graphite is scaly,
This is because it is essentially gasified at high temperature and then carburized and diffused into the product, and then to its composition. Natural graphite with less impurities is required here, but there is no need to limit the particle size. .
【0014】[0014]
【実施例】超高圧アトマイズ法で得られた平均粒径8ミ
クロンの純Cu微粉末と,Cを0.05重量%含有する
平均粒径5ミクロンのカ−ボニル鉄粉と,Cを0.9重
量含有する平均粒径5ミクロンのカ−ボニル鉄粉と,C
を0,01重量%以下含有する平均粒径5ミクロンのカ
ーボニルニッケル粉と、平均粒径22ミクロンの天然黒
鉛粉末とを用いて、表1に提示した組成になる様に金属
原料を秤量すると共に、この金属原料の92重量部に対
して8重量部に当たる重量の有機バインダー(この場
合、当該有機バインダ−はポリエチレン30重量%,パ
ラフィンワックス60重量%及びステアリン酸10重量
%となる様に秤量した)総量10Kgの原料を、直径が
300mmであるプラネタリーミキサーの混練槽に逐次
投入し、回転数を20rpmに設定した後、摂氏100
度で1時間の混練処理を施し,さらに、この混練物を直
径5mmのペレットに造粒して成形原料とした。DESCRIPTION OF THE PREFERRED EMBODIMENTS Pure Cu fine powder having an average particle diameter of 8 μm obtained by an ultra-high pressure atomizing method, carbonyl iron powder having an average particle diameter of 5 μm containing 0.05% by weight of C, and 0.1 μm of C. Carbonyl iron powder having an average particle size of 5 microns containing 9 wt.
Of carbonyl nickel powder having an average particle size of 5 μm containing 0.01% by weight or less and natural graphite powder having an average particle size of 22 μm, and weighing a metal raw material so as to have the composition shown in Table 1. An organic binder weighing 8 parts by weight with respect to 92 parts by weight of the metal raw material (in this case, the organic binder was weighed so as to be 30% by weight of polyethylene, 60% by weight of paraffin wax and 10% by weight of stearic acid). ) Raw materials having a total amount of 10 kg were sequentially charged into a kneading tank of a planetary mixer having a diameter of 300 mm, and the rotation speed was set to 20 rpm.
The mixture was subjected to a kneading treatment at a temperature of 1 hour, and the kneaded product was granulated into pellets having a diameter of 5 mm to obtain a forming raw material.
【0015】上記の成形原料を、射出圧力を600Kg
/cm2 、射出速度を30mm/sec、射出温度を摂
氏90度の設定条件下にて金型に射出成形し、材料引っ
張り試験片の成形体を製作した。[0015] The above molding material is injected at an injection pressure of 600 kg.
/ Cm 2 , an injection speed of 30 mm / sec, and an injection temperature of 90 ° C. were injection-molded into a mold to produce a molded product of a material tensile test piece.
【0016】上記の成形体を窒素雰囲気中で摂氏300
度に加熱することによって、先ず成形体より有機バイン
ダーを除去し、その後、真空度を5×10-2Torrに
設定した半連続式の真空焼結炉を用いて、摂氏1250
度で1時間の焼結処理を施し、JSPM標準2−64に
基づいた粉末焼結体引っ張り試験片を得た。[0016] The above-mentioned molded body is cooled in a nitrogen atmosphere to 300 ° C.
The organic binder is first removed from the molded body by heating to a temperature of 1250 ° C., and then using a semi-continuous vacuum sintering furnace in which the degree of vacuum is set to 5 × 10 −2 Torr.
The sintered body was subjected to a sintering treatment at a temperature of 1 hour to obtain a tensile test piece of the powdered sintered body based on JSPM Standard 2-64.
【0017】次いで、上記の引っ張り試験片を各組成の
成形原料について10本づつ用意し、島津オートグラフ
AE−5000を用いて試験片の引張破断強度と伸びを
測定して表1を得た。Next, ten tensile test pieces were prepared for each molding material of each composition, and the tensile breaking strength and elongation of the test pieces were measured using Shimadzu Autograph AE-5000 to obtain Table 1.
【0018】[0018]
【表1】 [Table 1]
【0019】この表1より従来、高強度鋼部材として利
用されていたFe−Ni−C系合金の部材に比較して、
本発明合金は伸びは多少減少するものの,引張破断強度
は大幅に改善されている事が明らかになった。また,C
u,Cが本発明範囲外の合金(表中△印は範囲外値を示
す・・・比較例1乃至3)は引張破断強度もしくは伸び
のいずれに於いて市場の要求値を満たさず(表中*印は
要求値以下を示す)実用性のないことが判明した。From Table 1, as compared with the Fe-Ni-C alloy member conventionally used as a high-strength steel member,
Although the elongation of the alloy of the present invention was slightly reduced, the tensile strength at break was significantly improved. Also, C
The alloys in which u and C are out of the range of the present invention (the symbols in the table show values outside the range ... Comparative Examples 1 to 3) do not satisfy the market requirements in either tensile strength or elongation (Table 1). (* Indicates the required value or less)) It was found that it was not practical.
【0020】尚、上記の試験片について別途に測定した
相対密度比は何れも92〜95%の値を示して居り、本
発明品を利用する分野に於いては充分にその機能を満足
するものであった。Incidentally, the relative density ratios of the above-mentioned test pieces, which were separately measured, each showed a value of 92 to 95%, which sufficiently satisfied the function in the field of using the product of the present invention. Met.
【0021】[0021]
【発明の効果】本発明の実施により、従来品を上回る性
能を持つた射出成形高強度鋼部材を供給する事が可能に
なり、当該部材を組み込んでいる製品の機能性向上並び
に形状縮小化に対して貢献するところ大なるものがあ
る。According to the present invention, it is possible to supply an injection-molded high-strength steel member having a performance exceeding that of a conventional product, thereby improving the functionality and reducing the size of a product incorporating the member. There is a great deal to contribute to.
Claims (2)
ボニルFe粉と、平均粒径が20ミクロン以下であるC
u粉と、天然黒鉛粉と、を調合して1〜10重量%のC
uと、0.3〜1.0重量%のCと、残部が不可避的不
純物を含んだFeとからなる合金組成の金属原料粉を得
ること、この金属原料粉91.8重量%〜92.2重量
%に対して有機バインダー7.8〜8.2重量%を加え
て混練機により混練すること、この混練物を予め用意し
た型に射出成形して得た成形体を300℃までの不活性
雰囲気中で加熱することによって成形体より有機バイン
ダーを除去すること、その後この脱バインダー成形体を
真空焼結炉中で焼結処理することを特徴とする射出成形
法による高強度鋼部材の製造方法。1. Carbonyl Fe powder having an average particle size of 10 μm or less, and C having an average particle size of 20 μm or less.
u powder and natural graphite powder are mixed to form 1 to 10% by weight of C.
u, 0.3 to 1.0% by weight of C, and the balance being Fe containing an unavoidable impurity, to obtain a metal raw material powder having an alloy composition of 91.8% by weight to 91.8% by weight of this metal raw material powder. 7.8 to 8.2% by weight of an organic binder is added to 2% by weight, and the mixture is kneaded by a kneading machine. A molded body obtained by injection molding the kneaded material into a previously prepared mold is heated to 300 ° C. Production of high-strength steel members by injection molding, characterized in that the organic binder is removed from the compact by heating in an active atmosphere, and then the binder-free compact is sintered in a vacuum sintering furnace. Method.
%と、パラフィンワックス60重量%と、ステアリン酸
10重量%とからなることを特徴とする請求項2記載の
射出成形法による高強度鋼部材の製造方法。2. The method according to claim 2, wherein the organic binder comprises 30% by weight of polyethylene, 60% by weight of paraffin wax, and 10% by weight of stearic acid. .
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3224552A JP2745889B2 (en) | 1991-08-08 | 1991-08-08 | Method of manufacturing high-strength steel member by injection molding method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3224552A JP2745889B2 (en) | 1991-08-08 | 1991-08-08 | Method of manufacturing high-strength steel member by injection molding method |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0543907A JPH0543907A (en) | 1993-02-23 |
JP2745889B2 true JP2745889B2 (en) | 1998-04-28 |
Family
ID=16815575
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP3224552A Expired - Lifetime JP2745889B2 (en) | 1991-08-08 | 1991-08-08 | Method of manufacturing high-strength steel member by injection molding method |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2745889B2 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4121383B2 (en) * | 2003-01-08 | 2008-07-23 | 三菱マテリアルPmg株式会社 | Iron-base metal bond excellent in dimensional accuracy, strength and sliding characteristics and method for manufacturing the same |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS53128513A (en) * | 1977-04-16 | 1978-11-09 | Sumitomo Electric Ind Ltd | Process for producing sintered steel |
-
1991
- 1991-08-08 JP JP3224552A patent/JP2745889B2/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
JPH0543907A (en) | 1993-02-23 |
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