JPH0711002B2 - Alloy steel powder with small dimensional variation in heat treatment and method for producing the same - Google Patents
Alloy steel powder with small dimensional variation in heat treatment and method for producing the sameInfo
- Publication number
- JPH0711002B2 JPH0711002B2 JP63039715A JP3971588A JPH0711002B2 JP H0711002 B2 JPH0711002 B2 JP H0711002B2 JP 63039715 A JP63039715 A JP 63039715A JP 3971588 A JP3971588 A JP 3971588A JP H0711002 B2 JPH0711002 B2 JP H0711002B2
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- JP
- Japan
- Prior art keywords
- alloy
- steel powder
- powder
- alloy steel
- less
- 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.)
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Links
- 239000000843 powder Substances 0.000 title claims description 73
- 229910000851 Alloy steel Inorganic materials 0.000 title claims description 39
- 238000010438 heat treatment Methods 0.000 title claims description 14
- 238000004519 manufacturing process Methods 0.000 title claims description 7
- 229910045601 alloy Inorganic materials 0.000 claims description 27
- 239000000956 alloy Substances 0.000 claims description 27
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 22
- 229910000831 Steel Inorganic materials 0.000 claims description 15
- 239000010959 steel Substances 0.000 claims description 15
- 238000009792 diffusion process Methods 0.000 claims description 14
- 229910052802 copper Inorganic materials 0.000 claims description 12
- 229910052759 nickel Inorganic materials 0.000 claims description 11
- 229910052750 molybdenum Inorganic materials 0.000 claims description 10
- 239000000203 mixture Substances 0.000 claims description 9
- 229910052742 iron Inorganic materials 0.000 claims description 6
- 238000005275 alloying Methods 0.000 claims description 4
- 239000002245 particle Substances 0.000 claims description 4
- 239000002184 metal Substances 0.000 claims description 3
- 229910052751 metal Inorganic materials 0.000 claims description 3
- 150000001875 compounds Chemical class 0.000 claims description 2
- 239000007788 liquid Substances 0.000 claims description 2
- 229910000640 Fe alloy Inorganic materials 0.000 claims 1
- 229910001566 austenite Inorganic materials 0.000 description 8
- 239000000126 substance Substances 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- 238000004663 powder metallurgy Methods 0.000 description 7
- 238000010791 quenching Methods 0.000 description 7
- 230000000717 retained effect Effects 0.000 description 7
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- 230000000171 quenching effect Effects 0.000 description 6
- 239000002131 composite material Substances 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- 239000011159 matrix material Substances 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 238000000137 annealing Methods 0.000 description 2
- 229910001563 bainite Inorganic materials 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- 229910001182 Mo alloy Inorganic materials 0.000 description 1
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000000265 homogenisation Methods 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000005496 tempering Methods 0.000 description 1
- XOOUIPVCVHRTMJ-UHFFFAOYSA-L zinc stearate Chemical compound [Zn+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O XOOUIPVCVHRTMJ-UHFFFAOYSA-L 0.000 description 1
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は各種焼結部品のうち、特に高精度が要求される
部品の製造に使用される粉末冶金用合金鋼粉に関するも
のである。TECHNICAL FIELD The present invention relates to an alloy steel powder for powder metallurgy, which is used in the production of various sintered parts that require particularly high precision.
自動車用ギア等の高強度、高精度部品を粉末冶金で製造
する場合、高強度化を図るためには合金元素の添加を行
い、さらに焼入焼戻し処理する必要がある。When powder metallurgy is used to manufacture high-strength, high-precision parts such as automobile gears, it is necessary to add an alloying element and then quench and temper to enhance the strength.
純鉄粉中に合金成分を固溶させて合金鋼粉を製造する予
合金法では、寸法精度は高いものの鋼粉の圧縮性を損な
うことが多く、その場合、高い焼結密度が得られなくな
り、結果的に強度向上が望めない。In the pre-alloying method of producing alloy steel powder by solid solution of alloy components in pure iron powder, the dimensional accuracy is high, but the compressibility of steel powder is often impaired, in which case high sintered density cannot be obtained. , As a result, the strength cannot be improved.
それに対し、例えば特公昭45−9649号において提案され
ているように、純鉄粉にNi,Cu,Mo等の合金成分粉末を拡
散付着することによって上述の問題を克服する技術（以
下複合合金法と称す）が開示されている。この方法によ
って製造された複合合金鋼粉は圧縮性は優れるものの、
異種金属粉を混粉後加熱することにより拡散を生じせし
め、部分的に合金化するだけなので、成分的に完全に均
一な予合金法に較べ、どうしても組織の不均一性を生
じ、製品の寸法変化のばらつきの原因となる。このよう
な鋼粉では圧縮性が高く高強度化は図れるが、高強度と
高精度の両特性を兼ね備えることができない。On the other hand, as proposed in Japanese Patent Publication No. 45-9649, for example, a technique for overcoming the above-mentioned problems by diffusing and adhering alloy component powders such as Ni, Cu and Mo to pure iron powder (hereinafter referred to as a composite alloy method) (Referred to as) is disclosed. Although the composite alloy steel powder produced by this method has excellent compressibility,
By mixing different kinds of metal powders and heating them to cause diffusion and only partially alloy them, nonuniformity of the structure is inevitably generated compared to the prealloying method in which the composition is completely uniform, and the product dimensions It causes variation in change. Although such steel powder has high compressibility and high strength, it cannot have both high strength and high precision characteristics.
また、本発明者らは先に高い圧縮性を有し、過剰浸炭を
抑制する粉末冶金用合金鋼粉およびその製造法（特開昭
61−130401）を開示したが、その内容は、焼結前に、N
i、Moなどの合金成分を鉄鋼粉表面への付着状態を制限
した状態で拡散付着せしめる粉末冶金用合金鋼粉であ
り、得られる焼結体は過剰浸炭の抑制によって優れた特
性（高い衝撃値および引張り強さ）を有しているが、一
方、熱処理のときの寸法変化のばらつきの低減が要請さ
れている。In addition, the present inventors previously found that the alloy steel powder for powder metallurgy which has high compressibility and suppresses excessive carburization and a method for producing the same (Japanese Patent Laid-Open Publication No. Sho.
61-130401), the content of which is
It is an alloy steel powder for powder metallurgy that diffuses and adheres alloy components such as i and Mo to the surface of iron and steel powder in a restricted state, and the resulting sintered body has excellent properties (high impact value) by suppressing excessive carburization. And tensile strength), on the other hand, it is required to reduce the variation in dimensional change during heat treatment.
本発明は以上の事情に鑑みてなされたもので、高強度焼
結熱処理材が得られるような高い圧縮性を有し、かつ、
熱処理を施したときにも高精度が得られる粉末冶金用合
金粉およびその製造方法を提供することを目的とするも
のである。The present invention has been made in view of the above circumstances, has high compressibility such that a high-strength heat-treated sintered material is obtained, and
It is an object of the present invention to provide an alloy powder for powder metallurgy and a method for producing the same, which can obtain high accuracy even when subjected to heat treatment.
本発明者らは、複合合金鋼粉を成形し、焼結し、焼入焼
戻しするプロセスで製品化するに当り、部品精度の低下
は、 （１）部品の内外部で焼入時の冷却速度が異なり、組織
の不均一が生じること、および （２）残留オーステナイトの大きさの分布が広く、部分
的に大きな残留オーステナイト相が存在するため寸法歪
のばらつきを生じること、 に原因があることを見い出した。When the present inventors commercialize the composite alloy steel powder by molding, sintering, and quenching and tempering, the accuracy of the parts is reduced by (1) cooling rate during quenching inside and outside the part Are different from each other, and the non-uniformity of the structure occurs, and (2) the distribution of the size of the retained austenite is wide and the dimensional strain varies due to the presence of a large retained austenite phase partially. I found it.
本発明者らは、この解決策を鋭意研究した結果、 通常の焼入時に生じる冷却速度のばらつきの範囲で
も、均一なマルテンサイト組織を有するように合金成分
を選定すること、 鉄鋼粉に対する各合金成分の拡散付着濃度を均一化
し、残留オーステナイトの大きさの分布を小さくするこ
と、 が極めて有効であることを見い出した。As a result of diligent research on this solution, the inventors have selected alloy components so as to have a uniform martensite structure even within the range of variation in cooling rate that occurs during normal quenching, and each alloy for steel powder. It has been found that it is extremely effective to uniformize the diffusion adhesion concentration of the components and reduce the size distribution of the retained austenite.
その際、合金添加するCuを含む全成分が均一に拡散付着
する必要がある。この点において本発明は高い強度、靭
性とともに、優れた寸法精度を有する技術を提供する。
すなわち、本条件下において得られる合金鋼粉により、
高い引張り強さとともに優れた寸法精度を有する焼結熱
処理材が得られる。At that time, it is necessary to uniformly diffuse and adhere all components including Cu added to the alloy. In this respect, the present invention provides a technique having high strength and toughness as well as excellent dimensional accuracy.
That is, the alloy steel powder obtained under these conditions,
It is possible to obtain a sintered heat-treated material having high tensile strength and excellent dimensional accuracy.
本発明の具体的構成は次のとおりである。The specific configuration of the present invention is as follows.
すなわち、本発明は、鉄鋼粉表面上にCu,Ni,Moの各合金
成分を単独に含む粉末を同時に拡散付着させた合金鉄鋼
粉であって、合金元素であるCuとNiとMoとの合計が7.2
重量％を超え8.8重量％未満、Niが5.0重量％を超え7.0
重量％未満、Cuが1.46重量％以上2.30重量％以下からな
り、かつ粒径44μｍ以下の合金鋼粉に対する各合金成分
の拡散付着濃度が合金鋼粉全体の拡散付着濃度の2.2倍
以下の濃度範囲にあることを特徴とする熱処理における
寸法変化のばらつきの小さい合金鋼粉である。また、本
発明の粉末冶金用合金鋼粉の製造方法は、Cu,NiおよびM
oをその合計で7.2重量％を超え8.8重量％未満、Niを5.0
重量％を超え7.0重量％未満、Cuを1.46重量％以上2.30
重量％以下を含むように、各合金成分を単独に含む金属
粉末または化合物粉末を、それらの合金成分を含む粉末
に対して非可溶性の液に分散させた後、残余重量％の鉄
粉と混合し、熱処理により、その鉄鋼粉表面上にそれら
の合金成分を拡散付着させて、粒径44μｍ以下の合金鋼
粉に対する各合金成分の拡散付着濃度が合金鋼粉全体の
拡散付着濃度の2.2倍以下の濃度範囲にすることを特徴
とする熱処理における寸法変化のばらつきの小さい合金
鋼粉を得る方法である なお、本発明において拡散付着させるとは、合金成分粉
末中からその合金成分の一部が鉄鋼粉中に拡散して、他
部の合金成分粉末が鉄鋼粉に結合付着した状態にするこ
とを意味する。That is, the present invention is an iron and steel powder that simultaneously diffuses and adheres powder containing Cu, Ni, and Mo alloys alone to the iron and steel powder surface, and the sum of alloy elements Cu, Ni, and Mo. Is 7.2
Over 8.8% by weight, Ni over 5.0% by weight and 7.0
Less than 1 wt% Cu, 1.46 wt% or more and 2.30 wt% or less, and the concentration range where the diffusion adhesion concentration of each alloy component to alloy steel powder with a grain size of 44 μm or less is 2.2 times or less than the diffusion adhesion concentration of the entire alloy steel powder. The alloy steel powder has a small variation in dimensional change during heat treatment. Further, the manufacturing method of the alloy steel powder for powder metallurgy of the present invention, Cu, Ni and M
o is more than 7.2 wt% and less than 8.8 wt% in total, Ni is 5.0
More than 7.0% by weight and less than 1.46% by weight of Cu 2.30
Metal powder or compound powder containing each alloy component alone so as to contain less than wt% is dispersed in a liquid insoluble in the powder containing those alloy components, and then mixed with the remaining wt% of iron powder. Then, the alloy components are diffused and adhered to the surface of the steel powder by heat treatment, and the diffusion adhesion concentration of each alloy component to the alloy steel powder with a particle size of 44 μm or less is 2.2 times or less than the diffusion adhesion concentration of the entire alloy steel powder. Is a method for obtaining an alloy steel powder having a small variation in dimensional change in the heat treatment, which is characterized in that the concentration range of the alloy component powder is diffused and adhered in the present invention. It means that the alloy component powder of the other part is bonded and adhered to the iron and steel powder by diffusing into the powder.
複合合金鋼粉焼結体の焼入焼戻し材の寸法歪のばらつき
を低減するには、先ず、焼入後のマトリックスの組織を
均一化する必要がある。この均一化は、化学組成による
ところが大きく、Cu,Ni,Moを合金元素とする場合に、本
発明者らが種々検討したところ、先ずCuとNiとMoの合計
量を7.2重量％を超え8.8重量％未満にする必要があるこ
とが見い出された。7.2重量％以下であると、焼入後の
マトリックス組織は部分的にベイナイトを呈するように
なり、寸法歪のばらつきが増大する。一方、8.8重量％
以上になると残留オーステナイト量が増加し、むしろ寸
法歪のばらつきは増大する。In order to reduce the variation in dimensional strain of the quenched and tempered material of the composite alloy steel powder sintered body, it is first necessary to make the matrix structure uniform after quenching. This homogenization largely depends on the chemical composition, and when Cu, Ni, and Mo are alloying elements, the present inventors have made various studies, and first, the total amount of Cu, Ni, and Mo exceeds 7.2% by weight and exceeds 8.8. It has been found that it must be less than wt%. If it is 7.2% by weight or less, the matrix structure after quenching will partially show bainite, and the variation in dimensional strain will increase. On the other hand, 8.8% by weight
If it becomes the above, the amount of retained austenite will increase and the variation of dimensional strain will rather increase.
Niはオーステナイト安定化元素であり、同時に焼入性増
加元素でもあるが、このNi量は5.0重量％を超え、7.0重
量％未満の範囲で寸法歪のばらつきを小さくすることが
見い出された。5.0重量％以下であると焼入後のマトリ
ックス組織は部分的にベイナイトを呈するようになり、
一方、7.0重量％以上であると残留オーステナイトが増
加し、寸法歪のばらつきは何れも増加する。Although Ni is an austenite stabilizing element and at the same time an element for increasing hardenability, it has been found that the variation in dimensional strain is reduced in the range where the Ni content exceeds 5.0% by weight and less than 7.0% by weight. If it is 5.0% by weight or less, the matrix structure after quenching will partially show bainite,
On the other hand, if it is 7.0% by weight or more, the retained austenite increases, and the variation in dimensional strain also increases.
次に、本発明のもう一つの大きな知見に基づくと、寸法
歪のばらつきを小さくするためには残留オーステナイト
の大きさの均一化を図ることが有効である。そのために
は、合金鋼粉粒子径44μｍ以下の微粒粉に対する拡散付
着濃度がCuを始めとする全成分について、合金鋼粉全体
に対する各合金成分の拡散付着濃度の各々2.2倍以下に
する必要がある。その理由は、微細な各合金粉の付着が
不十分な部分が鉄鋼粉粒子表面から脱落して、44μｍ以
下の鉄粉に対する各合金成分の濃度が増加し、合金鋼粉
全体の各合金成分の濃度の2.2倍を超える場合には、残
留オーステナイトの均一性が低下し、寸法歪のばらつき
が増加するからである。Next, based on another large finding of the present invention, it is effective to make the sizes of retained austenite uniform in order to reduce the variation in dimensional strain. For that purpose, it is necessary that the diffusion adhesion concentration of fine particles with an alloy steel powder particle diameter of 44 μm or less is not more than 2.2 times the diffusion adhesion concentration of each alloy component with respect to the entire alloy steel powder for all components including Cu. . The reason is that the portions where the fine alloy powders are not sufficiently adhered fall off from the surface of the iron and steel powder particles, and the concentration of each alloy component with respect to the iron powder of 44 μm or less increases. This is because if the concentration exceeds 2.2 times, the uniformity of retained austenite decreases, and the variation in dimensional strain increases.
実施例１〜４、比較例１〜６ 次に本発明について、実施例に従ってさらに具体的に説
明する。Examples 1 to 4 and Comparative Examples 1 to 6 Next, the present invention will be described more specifically according to Examples.
Cu粉、Ni酸化物およびMo酸化物をメチルアルコールに分
散させた後鉄粉と混合し、乾燥を経て水素ガス雰囲気中
にて1000℃で１時間還元焼鈍後解砕した。このときの化
学組成が第１表Ａ〜Ｄ（実施例鋼粉）および第２表Ｅ〜
Ｊ（比較例鋼粉）に示すような複合合金鋼粉を作製し
た。Cu powder, Ni oxide, and Mo oxide were dispersed in methyl alcohol, mixed with iron powder, dried, and then annealed at 1000 ° C. for 1 hour in a hydrogen gas atmosphere and then crushed. The chemical compositions at this time are Tables A to D (Example steel powder) and Tables 2 to E.
Composite alloy steel powder as shown in J (Comparative Steel Powder) was prepared.
次にこれらの鋼粉に黒鉛粉0.35重量％およびステアリン
酸亜鉛１重量％を混合し、7t/cm2の圧力で外径60mmφ、
内径20mmφ、高さ5.5mmのリング状試験片に成形した。
この成形体を1130℃で15分AXガス雰囲気中で焼結した
後、850℃で45分間カーボンポテンシャル0.8重量％の雰
囲気中で加熱して浸炭後、油中に焼入れ、さらに160℃
で60分の焼戻し処理を施した。Next, 0.35% by weight of graphite powder and 1% by weight of zinc stearate are mixed with these steel powders, and the outer diameter is 60 mmφ at a pressure of 7 t / cm 2 .
It was molded into a ring-shaped test piece having an inner diameter of 20 mmφ and a height of 5.5 mm.
This compact was sintered at 1130 ° C for 15 minutes in AX gas atmosphere, heated at 850 ° C for 45 minutes in an atmosphere of carbon potential 0.8% by weight, carburized, quenched in oil, and further heated at 160 ° C.
Then, it was tempered for 60 minutes.
これらの焼結熱処理材の引張強さを第１表および第２表
に併記した。また、これらの合金鋼粉の粒径44μｍ以下
の合金鋼粉に対するCu,Ni,Mo各成分の拡散付着度と鉄鋼
粉全体のそれとの比（以下R44/Tとする）を第３表に示
す。なお、これらの値は、焼鈍後解砕した粉末を44μｍ
以下でふるったものおよび未篩いのものについて通常の
化学分析を行って求めた。The tensile strengths of these sintered heat-treated materials are also shown in Tables 1 and 2. Table 3 shows the ratio of the diffusion adhesion of Cu, Ni, and Mo components to the alloy steel powder with a grain size of 44 μm or less and that of the entire steel powder (hereinafter referred to as R 44 / T ). Show. In addition, these values are 44 μm for the powder crushed after annealing.
It was determined by performing ordinary chemical analysis on the sieved and unsieved ones described below.
何れの鋼粉もR44/Tが2.2より小さく、均一性が良好であ
る。All steel powders have R44 / T values of less than 2.2 and good uniformity.
次にＡ〜Ｊ粉の焼結体に、上述の熱処理を施したときの
寸法歪のばらつきを標準偏差として表わし、Cu＋Ni＋Mo
量との関係を整理した結果を第１図に示す。Next, the variation of dimensional strain when the above-mentioned heat treatment is applied to the sintered bodies of A to J powders is expressed as standard deviation, and Cu + Ni + Mo
Fig. 1 shows the result of arranging the relationship with the amount.
本発明の化学組成の範囲において、寸法歪のばらつきが
極めて小さくなることが分る。It can be seen that the variation in dimensional strain is extremely small within the range of the chemical composition of the present invention.
比較例７〜９ Cu粉、Ni酸化物およびMo酸化物を乾式で鉄粉と混合後、
水素ガス雰囲気にて1000℃で１時間還元焼鈍後解砕し
て、第４表に化学組成を示す合金鋼粉Ｋ〜Ｍ（比較例７
〜９）を作製した。これらの合金鋼粉のR44/Tを第５表
に示す。化学組成は本発明範囲であるが、R44/Tは2.3〜
3.2と高い。Comparative Examples 7 to 9 Cu powder, Ni oxide and Mo oxide were dry mixed with iron powder,
Alloy steel powders KM having the chemical composition shown in Table 4 were crushed after reduction annealing at 1000 ° C. for 1 hour in a hydrogen gas atmosphere (Comparative Example 7).
.About.9) were produced. Table 5 shows R 44 / T of these alloy steel powders. Although the chemical composition is within the scope of the present invention, R 44 / T is 2.3 to
High as 3.2.
第２図には、上述のように製造した合金鋼粉を、先の条
件で焼結熱処理したときの、熱処理における寸法歪のば
らつきをCuについてのR44/Tで整理した結果を実施例１
〜４とともに示した。なお、焼結熱処理材の引張強さを
第４表に併記した。R44/Tが本発明範囲である2.2以下に
おいては、寸法歪のばらつきが極めて小さくなることが
分る。FIG. 2 shows the results of arranging the dimensional strain variation in the heat treatment when the alloy steel powder produced as described above was sintered and heat treated under the previous conditions by R 44 / T for Cu.
˜4. The tensile strength of the heat-treated sintered material is also shown in Table 4. It can be seen that when R 44 / T is 2.2 or less, which is the range of the present invention, the variation in dimensional strain becomes extremely small.
比較例10 Ni酸化物、Mo酸化物を実施例１〜４と同様にメチルアル
コールに分散させた後鉄粉と混合した後、還元焼鈍後解
砕した。この合金鋼粉にCu粉を混合し、800℃水素雰囲
気中で１時間焼鈍してNi、Mo、Cuを拡散付着させた合金
鋼粉Ｎ（比較例10）を作製した。Comparative Example 10 Ni oxide and Mo oxide were dispersed in methyl alcohol in the same manner as in Examples 1 to 4, mixed with iron powder, and then reduced and annealed. Cu powder was mixed with this alloy steel powder and annealed in a hydrogen atmosphere at 800 ° C. for 1 hour to produce alloy steel powder N (Comparative Example 10) in which Ni, Mo and Cu were diffused and adhered.
この合金鋼粉の化学組成、引張り強さ、R44/Tを第４
表、第５表に示した。またこの合金鋼粉を実施例１〜４
と同一の条件で焼結したときの熱処理における寸法歪の
ばらつきを第２図に示した。比較例10では、引張り強さ
は比較的良好であるが、寸法歪のばらつきが実施例１〜
４に比して大きいことが分かる。The chemical composition, tensile strength, and R44 / T of this alloy steel powder are 4th.
The results are shown in Tables and 5. Further, this alloy steel powder was used in Examples 1 to 4
Fig. 2 shows variations in dimensional strain during heat treatment when sintered under the same conditions as in. In Comparative Example 10, the tensile strength is relatively good, but the variation in dimensional strain is
It turns out that it is larger than 4.
〔発明の効果〕 以上の説明により明らかなように、本発明の粉末冶金用
合金鋼粉は、焼結熱処理において、高強度と共に極めて
高い寸法精度を兼ね備えるものであり、自動車用のカム
ギアのような高強度および高い寸法精度を要求される部
品用として有用なものである。 [Effects of the Invention] As is clear from the above description, the alloy steel powder for powder metallurgy of the present invention has both high strength and extremely high dimensional accuracy in the sintering heat treatment, such as a cam gear for an automobile. It is useful for parts that require high strength and high dimensional accuracy.
第１図は化学組成（Cu＋Ni＋Mo量）が寸法変化のばらつ
きに及ぼす影響を示すグラフ、第２図は粒径44μｍ以下
の合金鋼粉に対するCu成分の拡散付着濃度と合金鋼粉全
体に対するCu成分の拡散、付着濃度の比（R44/T）が寸
法変化のばらつきに及ぼす影響を示すグラフである。Fig. 1 is a graph showing the influence of chemical composition (Cu + Ni + Mo amount) on the variation of dimensional change, and Fig. 2 is the diffusion adhesion concentration of Cu component to alloy steel powder with a grain size of 44 µm or less and Cu component to the entire alloy steel powder. 9 is a graph showing the effect of the ratio of diffusion and adhesion concentration (R 44 / T ) on the variation in dimensional change.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 小倉 邦明 千葉県千葉市川崎町１番地 川崎製鉄株式 会社技術研究本部内 (56)参考文献 特開 昭63−297502（ＪＰ，Ａ) ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kuniaki Ogura Kuniaki Ogura 1 Kawasaki-cho, Chiba-shi, Chiba Kawasaki Steel Co., Ltd. Technical Research Division (56) References JP-A-63-297502 (JP, A)
Claims (2)
に含む粉末を同時に拡散付着させた合金鉄鋼粉であっ
て、合金元素であるCuとNiとMoとの合計が7.2重量％を
超え8.8重量％未満、Niが5.0重量％を超え7.0重量％未
満、Cuが1.46重量％以上2.30重量％以下からなり、かつ
粒径44μｍ以下の合金鋼粉に対する各合金成分の拡散付
着濃度が合金鋼粉全体に対する前記各合金成分の拡散付
着濃度の2.2倍以下の濃度範囲にあることを特徴とする
熱処理における寸法変化のばらつきの小さい合金鋼粉。1. An iron and steel alloy powder in which powders each containing an alloy component of Cu, Ni, Mo alone are simultaneously diffused and adhered to the surface of the iron and steel powder, and the total of the alloying elements Cu, Ni and Mo is 7.2. Diffusion adhesion of each alloy component to alloy steel powder with a weight percentage of more than 8.8 wt%, Ni of more than 5.0 wt% and less than 7.0 wt%, Cu of 1.46 wt% to 2.30 wt% and a grain size of 44 μm or less An alloy steel powder having a small variation in dimensional change during heat treatment, characterized in that the concentration is within a concentration range of not more than 2.2 times the diffusion adhesion concentration of each alloy component with respect to the entire alloy steel powder.
量％を超え8.8重量％未満、Niを合金鋼粉中5.0重量％を
超え7.0重量％未満、Cuを1.46重量％以上2.30重量％以
下を含むように、各合金成分を単独に含む金属粉末また
は化合物を、それらの合金成分を含む粉末に対して非可
溶性の液に分散させた後、残余重量％の鉄粉と混合し、
熱処理により、その鉄鋼粉表面上にそれらの合金成分を
拡散付着させて、粒径44μｍ以下の合金鋼粉に対する各
合金成分の拡散付着濃度が合金鋼粉全体の拡散付着濃度
の2.2倍以下の濃度範囲にすることを特徴とする熱処理
における寸法変化のばらつきの小さい合金鋼粉の製造方
法。2. The total content of Cu, Ni and Mo is more than 7.2% by weight and less than 8.8% by weight in the alloy steel powder, Ni is more than 5.0% by weight and less than 7.0% by weight in the alloy steel powder, and Cu is 1.46% by weight or more. Disperse a metal powder or compound containing each alloy component alone so as to contain 2.30% by weight or less in a liquid that is insoluble in the powder containing those alloy components, and then mix with the remaining weight% iron powder. Then
By heat treatment, the alloy components are diffused and adhered on the surface of the steel powder, and the concentration of the diffuse adhesion of each alloy component to the alloy steel powder with a particle size of 44 μm or less is 2.2 times or less than the diffusion adhesion concentration of the entire alloy steel powder. A method for producing an alloy steel powder having a small variation in dimensional change during heat treatment, characterized in that the range is set.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63039715A JPH0711002B2 (en) | 1988-02-24 | 1988-02-24 | Alloy steel powder with small dimensional variation in heat treatment and method for producing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63039715A JPH0711002B2 (en) | 1988-02-24 | 1988-02-24 | Alloy steel powder with small dimensional variation in heat treatment and method for producing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01215904A JPH01215904A (en) | 1989-08-29 |
| JPH0711002B2 true JPH0711002B2 (en) | 1995-02-08 |
Family
ID=12560684
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63039715A Expired - Lifetime JPH0711002B2 (en) | 1988-02-24 | 1988-02-24 | Alloy steel powder with small dimensional variation in heat treatment and method for producing the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0711002B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002022903A1 (en) | 1999-03-30 | 2002-03-21 | Kawasaki Steel Corporation | Iron base mixed powder for high strength sintered parts |
| RU2524510C2 (en) * | 2008-12-23 | 2014-07-27 | Хеганес Аб (Пабл) | Production of diffusion-alloyed iron powder or iron-based powder, diffusion-alloyed powder, composition including diffusion-alloyed powder, compacted and sintered part made thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63297502A (en) * | 1987-05-29 | 1988-12-05 | Kobe Steel Ltd | High-strength alloy steel powder for powder metallurgy and its production |
-
1988
- 1988-02-24 JP JP63039715A patent/JPH0711002B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01215904A (en) | 1989-08-29 |
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