JP5310074B2 - Iron-based powder mixture for high-strength sintered parts of automobiles - Google Patents
Iron-based powder mixture for high-strength sintered parts of automobiles Download PDFInfo
- Publication number
- JP5310074B2 JP5310074B2 JP2009038553A JP2009038553A JP5310074B2 JP 5310074 B2 JP5310074 B2 JP 5310074B2 JP 2009038553 A JP2009038553 A JP 2009038553A JP 2009038553 A JP2009038553 A JP 2009038553A JP 5310074 B2 JP5310074 B2 JP 5310074B2
- Authority
- JP
- Japan
- Prior art keywords
- iron
- based powder
- powder mixture
- powder
- mass
- 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.)
- Active
Links
Description
本発明は、鉄粉、合金鋼粉などの鉄基粉末に、所定の添加材、さらには黒鉛粉および銅粉などの合金用粉末を混合した鉄基粉末混合物に関し、さらに詳しくは、焼結体において優れた被削性が得られ、特に自動車用高強度焼結部品の製造に用いて好適な粉末冶金用の鉄基粉末混合物に関するものである。 The present invention relates to an iron-based powder mixture in which iron-based powders such as iron powder and alloy steel powder are mixed with predetermined additives, and further powders for alloys such as graphite powder and copper powder. The present invention relates to an iron-based powder mixture for powder metallurgy that is particularly suitable for use in the production of high-strength sintered parts for automobiles.
自動車等の各種機械に採用される鉄系焼結部品は、鉄基粉末混合物を原料とし、歯車などの部品に広く採用されている。鉄基粉末混合物は、鉄基粉末に、銅粉や黒鉛粉、燐化鉄粉などの合金用粉末と、ステアリン酸亜鉛やアミドワックスなどの潤滑剤、さらに必要に応じて切削性改善用粉末を混合して製造するのが一般的である。そして、使用する潤滑剤は、鉄基粉末との混合性や焼結時の散逸性などを考慮して選択されてきた。 Iron-based sintered parts used in various machines such as automobiles are widely used in parts such as gears using an iron-based powder mixture as a raw material. The iron-based powder mixture consists of iron-based powders, alloy powders such as copper powder, graphite powder and iron phosphide powder, lubricants such as zinc stearate and amide wax, and, if necessary, powder for improving machinability. It is common to produce by mixing. The lubricant to be used has been selected in consideration of the miscibility with the iron-based powder and the dissipating property during sintering.
上記した鉄基粉末混合物は、金型に充填して圧粉成形され、さらに焼結を行うことによって、所望の形状の部品となる。こうして得られた焼結部品は、寸法精度が良く、複雑な形状のものを製造することができる。但し、非常に厳しい寸法精度が要求される焼結部品を製造する場合には、焼結した後に、さらに機械加工（例えば旋盤切削加工やドリル加工等）を施す必要がある。 The iron-based powder mixture described above is filled in a mold, compacted, and further sintered to form a part having a desired shape. The sintered parts obtained in this way have good dimensional accuracy and can be manufactured in complex shapes. However, when manufacturing a sintered part that requires extremely strict dimensional accuracy, it is necessary to perform further machining (for example, lathe cutting or drilling) after sintering.
しかしながら、焼結部品は、内部に多数の空隙が存在するため、工具には断続的な衝撃が加えられ、また伝熱性が低いため、工具表面での摩擦発熱が放出されず、工具劣化が促進されることから、工具寿命が著しく短い。その結果、機械加工費が増大し、焼結部品の製造コストの上昇を招く。 However, sintered parts have many voids inside, so intermittent impact is applied to the tool and heat transfer is low, so frictional heat generation on the tool surface is not released and tool deterioration is accelerated. Therefore, the tool life is remarkably short. As a result, the machining cost increases and the manufacturing cost of the sintered part increases.
粉末冶金用の鉄基粉末混合物に、予め快削成分（例えばＳ、MnＳ等）を添加することによって、焼結部品の切削性が改善されることは従来から知られている。この快削成分は、切り屑を容易に破断させる効果、あるいは切削工具に薄い保護膜を形成して切削工具（特にすくい面）の潤滑性を高める効果を有している。 It has been conventionally known that the machinability of sintered parts is improved by adding a free-cutting component (for example, S, MnS, etc.) in advance to an iron-based powder mixture for powder metallurgy. This free-cutting component has an effect of easily breaking chips, or an effect of improving the lubricity of a cutting tool (particularly a rake face) by forming a thin protective film on the cutting tool.
例えば、非特許文献１には、添加した低融点のSiO2−CaO−Al2O3系の複合酸化物が、切削時の摩擦発熱によって軟化することにより、切削工具に薄い保護膜が形成される結果、切削工具（特にすくい面）の潤滑性が高まり、工具の摩耗が低減することが開示されている。
しかしながら、切削速度、切込み量、送り等の切削条件によって摩擦発熱が異なり、複合酸化物の軟化状態が変わること、さらに工具の材質と複合酸化物の濡れ性が異なることから、工具表面に適切な状態で保護膜が形成しない場合があり、切削条件によっては、切削改善効果が得られない、という問題があった。また、これらの添加物は、切屑の微細化効果はなく、切屑の排出性が悪いため、ドリル加工では切削性が改善されず、切削加工の種類が旋盤切削加工に限定されるという不利があった。さらに、MnＳ、Ｓなどの硫化物は、旋盤切削性およびドリル切削性のいずれの切削性をも改善できる添加材として知られているが、添加した焼結体の機械的強度が低下するといった問題もあった。
For example, in Non-Patent Document 1, a thin protective film is formed on a cutting tool by softening the added low melting point SiO 2 —CaO—Al 2 O 3 composite oxide by frictional heat generation during cutting. As a result, it is disclosed that the lubricity of a cutting tool (especially the rake face) is increased and the wear of the tool is reduced.
However, frictional heat generation varies depending on cutting conditions such as cutting speed, depth of cut, feed, etc., the softening state of the complex oxide changes, and the wettability of the tool material and the complex oxide differs. In some cases, the protective film may not be formed, and depending on the cutting conditions, there is a problem that the cutting improvement effect cannot be obtained. In addition, these additives have the disadvantage that there is no chip refinement effect and chip discharge is poor, so drilling does not improve cutting performance and the type of cutting is limited to lathe cutting. It was. Furthermore, sulfides such as MnS and S are known as additives that can improve both the machinability of lathe machinability and drill machinability, but the problem is that the mechanical strength of the added sintered body is reduced. There was also.
本発明は、上記の問題を有利に解決するもので、鉄基粉末に予め快削成分を添加することにより、旋盤切削性およびドリル切削性に優れ、かつ機械的強度が良好な自動車の高強度焼結部品を製造するのに好適な粉末冶金用の鉄基粉末混合物を提案することを目的とする。 The present invention advantageously solves the above problem, and by adding a free-cutting component to the iron-based powder in advance , the high strength of an automobile having excellent lathe and drill machinability and good mechanical strength. The object is to propose an iron-based powder mixture for powder metallurgy suitable for producing sintered parts.
さて、発明者らは、上記の問題を解決する方策として、旋盤切削性およびドリル切削性に優れ、しかも機械的強度が良好な焼結体を得るための鉄基粉末混合物の添加材について、鋭意検討を重ねた。
その結果、添加材として、MnＳ、MoＳおよびCaF2のうちから選んだ少なくとも２種とエンスタタイトとを複合添加した場合に、さらには好ましくは金属石鹸を併せて添加した場合に、旋盤切削性およびドリル切削性が改善され、しかも機械的強度が良好な焼結体が得られるとの知見を得た。
本発明は上記の知見に立脚するものである。
Now, as a measure for solving the above problems, the inventors have earnestly studied about an additive for an iron-based powder mixture for obtaining a sintered body having excellent lathe machinability and drill machinability and good mechanical strength. Repeated examination.
As a result, when adding at least two selected from MnS, MoS, and CaF 2 and enstatite as an additive, and preferably adding metal soap together, lathe machinability and It was found that a sintered body with improved drill machinability and good mechanical strength can be obtained.
The present invention is based on the above findings.
すなわち、本発明の要旨構成は次のとおりである。
１．平均粒径が80〜100μmの鉄基粉末に、添加材として、平均粒径がそれぞれ１〜10μm、５〜20μmおよび10〜50μmのMnＳ、MoＳおよびCaF2のうちから選んだ少なくとも２種と、平均粒径が１〜10μmのエンスタタイトとを添加し、さらに金属石鹸および合金用粉末を配合した鉄基粉末混合物であって、
上記MnＳ、MoＳおよびCaF 2 のうちから選んだ少なくとも２種とエンスタタイトの鉄基粉末混合物全体に対する添加量がそれぞれ0.005〜0.995mass％で、かつこれらの合計量が0.01〜1.0mass％で、上記金属石鹸の鉄基粉末混合物全体に対する配合量が0.02〜1.0mass％で、上記合金用粉末の鉄基粉末混合物全体に対する配合量が0.1〜５mass％であることを特徴とする自動車の高強度焼結部品用の鉄基粉末混合物。
That is, the gist configuration of the present invention is as follows.
1. At least two kinds selected from MnS, MoS and CaF 2 having an average particle diameter of 1 to 10 μm , 5 to 20 μm and 10 to 50 μm, respectively , as an additive to an iron-based powder having an average particle diameter of 80 to 100 μm ; An iron-based powder mixture in which enstatite having an average particle diameter of 1 to 10 μm is added , and metal soap and alloy powder are further blended,
Addition amount of at least two kinds selected from MnS, MoS and CaF 2 and enstatite to the whole iron-based powder mixture is 0.005 to 0.995 mass%, respectively, and the total amount thereof is 0.01 to 1.0 mass%. High strength sintering of an automobile characterized in that the blending amount of the metal soap with respect to the entire iron-based powder mixture is 0.02 to 1.0 mass%, and the blending amount of the alloy powder with respect to the entire iron-based powder mixture is 0.1 to 5 mass%. Iron-based powder mixture for parts .
本発明によれば、機械的強度が良好で、かつ切削性、すなわち旋盤切削性およびドリル切削性に優れる焼結体を実現し得る鉄基粉末混合物を得ることができる。 ADVANTAGE OF THE INVENTION According to this invention, the iron-base powder mixture which can implement | achieve the sintered compact which is favorable in mechanical strength and excellent in machinability, ie, lathe machinability, and drill machinability can be obtained.
以下、本発明を具体的に説明する。
まず、本発明の鉄基粉末混合物の原料について説明する。
本発明において、鉄基粉末としては、アトマイズ鉄粉や還元鉄粉などの純鉄粉、または部分拡散合金化鋼粉および完全合金化鋼粉、さらには完全合金化鋼粉に合金成分を部分拡散させたハイブリッド鋼粉などが例示される。
Hereinafter, the present invention will be specifically described.
First, the raw material of the iron-based powder mixture of the present invention will be described.
In the present invention, as iron-based powder, pure iron powder such as atomized iron powder and reduced iron powder, or partially diffused alloyed steel powder and fully alloyed steel powder, and further partially diffused alloy components in fully alloyed steel powder. The hybrid steel powder etc. which were made to be illustrated are illustrated.
また、合金用粉末としては、黒鉛粉末、Cu，Mo，Niなどの金属粉末、ボロン粉末および亜酸化銅粉末などが例示される。これらの合金用粉末を鉄基粉末に混合させることにより焼結体の強度を上昇させることができる。
この合金用粉末の配合量は、鉄基粉末混合物全体に対し0.1〜５mass％とする。というのは、合金用粉末を0.1mass％以上配合することにより、得られる焼結体の強度が有利に向上し、一方５mass％を超えると焼結体の寸法精度が低下するからである。
Examples of the alloy powder include graphite powder, metal powder such as Cu, Mo, and Ni, boron powder, and cuprous oxide powder. The strength of the sintered body can be increased by mixing these alloy powders with the iron-based powder.
The amount of the alloying powder shall be the 0.1～5Mass% relative to the total iron-based powder mixture. This is because, by adding 0.1 mass% or more of the alloy powder, the strength of the obtained sintered body is advantageously improved, while when it exceeds 5 mass%, the dimensional accuracy of the sintered body is lowered.
さて、本発明では、添加材として、MnＳ、MoＳおよびCaF2のうちから選んだ少なくとも２種とエンスタタイトとを複合添加することが重要である。ここに、エンスタタイトとしては、単斜晶系の結晶構造を有することが好ましい。なお、不可避的な不純物として、クリストバライトSiO2を含んでも構わない。 In the present invention, it is important to add at least two selected from MnS, MoS and CaF 2 and enstatite as an additive. Here, the enstatite preferably has a monoclinic crystal structure. Note that cristobalite SiO 2 may be included as an inevitable impurity.
次に、これら添加材の切削性改善機構について述べる。
MnＳ、MoＳ、CaF2は、鉄系材料との反応性が低く、また焼結中に化学変化を起こさないため、焼結体中で析出物として存在する。従って、切削時、切屑生成部で応力集中点となって切屑を微細化する。切屑の微細化は、ドリル切削においては、切屑の排出を促進し、ドリル寿命を延ばす。また、旋盤切削加工においては、切屑と工具の接触面積を低減するため、主としてすくい面の工具摩耗を低減する。
Next, the machinability improving mechanism of these additives will be described.
MnS, MoS, and CaF 2 have low reactivity with iron-based materials and do not cause chemical changes during sintering, and therefore exist as precipitates in the sintered body. Therefore, at the time of cutting, it becomes a stress concentration point in the chip generation part and refines the chip. The refinement of chips promotes the discharge of chips in drill cutting and extends the drill life. In lathe cutting, the tool wear on the rake face is mainly reduced in order to reduce the contact area between the chips and the tool.
MnＳ、MoＳ、CaF2は、それぞれ異なる粒度分布のものとし、異なる粒度分布の少なくとも２種を添加材として配合し、その配合比率を適宜調整することによって、焼結体の空隙の分布に相当する粒度分布とすることができる。その結果、添加材が、焼結体の空隙中に好適に充填され、結果として焼結体の空孔比率を下げ、切削時の断続切削を低減する効果を発揮する。
ここに、MnＳ、MoＳ、CaF2の好適粒径は、鉄基粉末の粒径に応じて変化するとはいえ、鉄基粉末の平均粒径が80〜100μmの場合には、それぞれ平均粒径で１〜10μm、5〜20μm、10〜50μmとする。
なお、上記平均粒径は、JIS R 1629に準拠したレーザ回折・散乱法により粒子径分布を測定し、体積基準の積算分率における50％径を用いる。
MnS, MoS, and CaF 2 have different particle size distributions, and at least two of the different particle size distributions are blended as additives, and the blending ratio is appropriately adjusted to correspond to the void distribution in the sintered body. It can be a particle size distribution. As a result, the additive is suitably filled in the voids of the sintered body, and as a result, the pore ratio of the sintered body is lowered, and the effect of reducing intermittent cutting during cutting is exhibited.
Here, MnS, MoS, preferred particle size of the CaF 2 can be said to vary depending on the particle size of the iron-base powder, when the average particle size of the iron based powder is 80~100μm are each an average particle diameter 1~10μm, 5~20μm, it shall be the 10~50μ m.
As the average particle size, a particle size distribution is measured by a laser diffraction / scattering method in accordance with JIS R 1629, and a 50% diameter in a volume-based integrated fraction is used.
また、エンスタタイトは、滑石を焼成して得られた柔かい酸化物であり、切削時、切削表面で容易に変形し、工具表面で潤滑膜を形成する。このエンスタタイトを、MnＳ、MoＳおよびCaF2のうちから選ばれる少なくとも２種と共に添加することにより、切屑の排出性および工具表面の潤滑性が併せて改善され、ドリル加工および旋盤切削加工のいずれにおいても工具寿命を格段に向上することができる。なお、エンスタタイトの平均粒径は１〜10μmとする。 Enstatite is a soft oxide obtained by firing talc and easily deforms on the cutting surface during cutting to form a lubricating film on the tool surface. By adding this enstatite together with at least two selected from MnS, MoS and CaF 2 , both chip discharge and tool surface lubricity are improved, and in both drilling and lathe cutting Also, the tool life can be significantly improved. The average particle size of enstatite is shall be the 1~10μ m.
これらMnＳ、MoＳおよびCaF2のうちから選ばれる少なくとも２種とエンスタタイトの添加量は、鉄基粉末混合物全体に対しそれぞれ0.005〜0.995mass％、0.005〜0.995mass％で、かつこれらの合計量で0.01〜1.0 mass％とする。
というのは、MnＳ、MoＳ、CaF2等の添加量が0.005mass％に満たないと、切屑のチッピング効果が十分でなく、一方0.995mass％を超えると焼結体強度の低下が著しいからである。また、エンスタタイトの添加量が0.005mass％に満たないと、工具表面の潤滑効果が十分でなく、一方0.995mass％を超えると余剰のエンスタタイトが切削面に排出され、外観不良となるからである。さらに、これらの添加材の合計量が0.01mass％に満たないと、機械的強度の低下なしに焼結体の切削性を十分に向上させることが難しく、一方1.0mass％を超えると、成形体を焼結して得た焼結材の機械的強度を低下させることが懸念されるからである。
These MnS, addition amount of at least two and enstatite selected from among MoS and CaF 2 are each based on the entire iron-based powder mixture 0.005～0.995Mass%, at 0.005～0.995Mass%, and a total amount of It shall be the 0.01~1.0 mass%.
This is because if the amount of MnS, MoS, CaF 2 or the like is less than 0.005 mass%, the chipping effect of the chips is not sufficient, while if it exceeds 0.995 mass%, the strength of the sintered body is significantly reduced. . Also, if the amount of enstatite added is less than 0.005 mass%, the lubrication effect on the tool surface will not be sufficient, while if it exceeds 0.995 mass%, excess enstatite will be discharged to the cutting surface, resulting in poor appearance. is there. Furthermore, if the total amount of these additives is less than 0.01 mass%, it is difficult to sufficiently improve the machinability of the sintered body without lowering the mechanical strength, while if it exceeds 1.0 mass%, the molded body This is because there is a concern about lowering the mechanical strength of the sintered material obtained by sintering.
また、本発明では、添加材中に、さらに金属石鹸を含有させるが、かかる金属石鹸を、エンスタタイトと共に添加することによって、成形体の圧縮性が改善されると同時に、成形時の抜出力が低減し、成形性が大幅に向上する。その理由は、次のとおりと考えられる。
すなわち、エンスタタイトは、成形時に鉄基粉末粒子間で剪断応力を受けた際に、結晶面に沿ってへき開し易く、そのため成形体内部の粒子間の摩擦抵抗が低減し、粒子間相互で動き易くなる、という潤滑効果によって、成形体の密度が向上するものと考えられる。また、成形体と金型間にエンスタタイトが存在すると、成形体抜出時に金型表面からの剪断応力を受けてへき開するため、金型表面での成形体のすべり易さが向上し、抜出力が低減するものと考えられる。
なお、これらの効果は、さらにへき開構造を有する有機化合物である金属石鹸を添加することによって、格段に改善される。
In the present invention, in the additive, but further contain a metal soap, such metallic soap, by adding together enstatite, at the same time the compression of the formed body is improved, ejection force during molding And formability is greatly improved. The reason is considered as follows.
That is, when enstatite is subjected to shear stress between iron-based powder particles during molding, it tends to cleave along the crystal plane, thus reducing the frictional resistance between particles inside the compact and moving between the particles. It is considered that the density of the molded body is improved by the lubricating effect of facilitating. Also, if enstatite is present between the molded body and the mold, it will be cleaved by the shear stress from the mold surface when the molded body is pulled out, improving the ease of sliding of the molded body on the mold surface. The output is considered to be reduced.
In addition, these effects are remarkably improved by adding metal soap which is an organic compound having a cleavage structure.
ここに、金属石鹸としては、ステアリン酸亜鉛、ステアリン酸リチウム、ステアリン酸カルシウムおよびステアリン酸マグネシウムなどが好適である。この金属石鹸の添加量は、鉄基粉末混合物全体に対し0.02〜1.0 mass％とする。というのは、添加量が0.02mass％に満たないとその添加効果に乏しく、一方1.0 mass％を超えると成形体強度の低下を招くからである。
また、エンスタタイトは、潤滑性能を発揮する他、鉄基粉末混合物を成形し、焼結する際に分解しない、すなわち有害な分解ガスを発生させず、焼結を阻害しないため、焼結体の機械的強度の向上にも有効に寄与する。
Here, as the metal soap, zinc stearate, lithium stearate, calcium stearate, magnesium stearate and the like are suitable. The amount of the metal soap, shall be the 0.02 to 1.0 mass% relative to the total iron-based powder mixture. This is because if the addition amount is less than 0.02 mass%, the effect of addition is poor, while if it exceeds 1.0 mass%, the strength of the compact is reduced.
Enstatite not only exhibits lubrication performance, but also does not decompose when an iron-based powder mixture is molded and sintered, that is, does not generate harmful decomposition gas and does not inhibit sintering. It also contributes to the improvement of mechanical strength.
次に、本発明の鉄基粉末混合物の製造方法について説明する。
鉄基粉末に、添加材として、MnＳ、MoＳおよびCaF2のうちから選んだ少なくとも２種とエンスタタイト、さらには金属石鹸および合金用粉末を加えて、１次混合する。ついで、１次混合後の混合物を、上記した添加材のうち少なくとも１種の添加材の融点以上に加熱しつつ撹拌し、混合しながら徐々に冷却して、鉄基粉末の表面に溶融した添加材によって合金用粉末やその他の添加材を固着させる。
なお、上記したMnＳ、MoＳおよびCaF2のうちから選んだ少なくとも２種やエンスタタイト、さらには金属石鹸などの添加材は、必ずしも全量を一度に添加する必要はなく、一部のみを添加して１次混合を行ったのち、残部を添加して２次混合することもできる。
また、混合手段としては、特に制限はなく従来から公知の混合機いずれもが使用できるが、加熱が容易な、高速底部撹拌式混合機、傾斜回転パン型混合機、回転クワ型混合機および円錐遊星スクリュー形混合機などは特に有利に適合する。
Next, the manufacturing method of the iron-based powder mixture of this invention is demonstrated.
At least two kinds selected from MnS, MoS, and CaF 2 and enstatite as well as metal soap and alloy powder are added to the iron-based powder as an additive, and are first mixed. Next, the mixture after the primary mixing is stirred while being heated above the melting point of at least one of the above-mentioned additives, gradually cooled while mixing, and added to the surface of the iron-based powder. The alloy powder and other additives are fixed by the material.
In addition, at least two kinds selected from the above-mentioned MnS, MoS, and CaF 2 and additives such as enstatite and metal soap do not necessarily need to be added all at once, and only a part thereof is added. After the primary mixing is performed, the remainder can be added to perform secondary mixing.
The mixing means is not particularly limited and any conventionally known mixer can be used. However, a high-speed bottom stirring mixer, an inclined rotary pan mixer, a rotary mulberry mixer, and a cone that can be easily heated can be used. A planetary screw type mixer or the like is particularly advantageously adapted.
次に、本発明の鉄基粉末混合物を用いた鉄基粉末成形体の製造方法および鉄基粉末焼結体の製造方法について説明する。
本発明の鉄基粉末混合物は、通常の成形方法で成形体とすることができる。すなわち、常温で成形することができる。とはいえ、鉄基粉末混合物や金型を加熱したり、金型に潤滑剤を塗布することは有利である。加熱雰囲気で成形を行う場合、鉄基粉末混合物や金型の温度は150℃未満とすることが好ましい。というのは、本発明に従う鉄基粉末混合物は圧縮性に富むので150℃未満の温度でも優れた成形性を示すが、150℃以上になると酸化による劣化が懸念されるからである。
Next, a method for producing an iron-based powder molded body and a method for producing an iron-based powder sintered body using the iron-based powder mixture of the present invention will be described.
The iron-based powder mixture of the present invention can be formed into a molded body by a normal molding method. That is, it can be molded at room temperature. Nevertheless, it is advantageous to heat the iron-based powder mixture or the mold or to apply a lubricant to the mold. When molding in a heated atmosphere, the temperature of the iron-based powder mixture and the mold is preferably less than 150 ° C. This is because the iron-based powder mixture according to the present invention has excellent compressibility and exhibits excellent moldability even at a temperature of less than 150 ° C., but at 150 ° C. or more, there is a concern about deterioration due to oxidation.
ついで、上記のようにして得られた高密度鉄基粉末成形体に、焼結処理を施して、高密度の焼結体とする。焼結処理については、特に限定されることはなく、従来公知の焼結処理方法いずれもが好適に使用できる。また、焼結処理後に、ガス浸炭熱処理や浸炭窒化処理等の熱処理を適用することも可能である。 Next, the high-density iron-based powder molded body obtained as described above is subjected to a sintering treatment to obtain a high-density sintered body. The sintering treatment is not particularly limited, and any conventionally known sintering treatment method can be suitably used. It is also possible to apply a heat treatment such as a gas carburizing heat treatment or a carbonitriding treatment after the sintering treatment.
以下、実施例に基づき本発明を具体的に説明する。
還元純粉末、0.8 mass％の天然黒鉛粉（平均粒径：５μm）および2.0 mass％の銅粉（平均粒径：25μm）に、各種添加材（１次添加材）を添加し、高速底部撹拌式混合機で混合しながら140℃に加熱した後、60℃以下に冷却し、さらに各種添加材（２次添加材）を添加し、500rpmで１分間撹拌後、混合機から混合粉末を排出した。１次および２次添加材の種類と添加量を、表１に併記する。添加材の添加量（質量部）は、鉄基粉末と天然黒鉛粉と銅粉との合計質量：100質量部に対する割合を外数で示したものであるが、内数（質量％）で表した数値とほぼ同じである。なお、MnＳ、MoＳ、CaF2およびエンスタタイト粉末の平均粒径はそれぞれ６μm、４μm、20μｍ、6μmであった。
また、標準材として、上記と同じ鉄基粉末、天然黒鉛粉および銅粉の組成の粉末に、潤滑剤としてステアリン酸亜鉛を合計で0.8mass％添加し、Ｖ型容器回転式混合機で混合した混合粉末を用意した(表１参照)。
Hereinafter, the present invention will be specifically described based on examples.
Add various additives (primary additive) to reduced pure powder, 0.8 mass% natural graphite powder (average particle size: 5 μm) and 2.0 mass% copper powder (average particle size: 25 μm), and stir at high speed at the bottom After heating to 140 ° C. while mixing with a mixer, cool to 60 ° C. or below, add various additives (secondary additives), stir at 500 rpm for 1 minute, and then discharge the mixed powder from the mixer . Table 1 shows the types and amounts of primary and secondary additives. The additive amount (parts by mass) of the additive is the total mass of the iron-based powder, natural graphite powder and copper powder: the ratio to the 100 parts by mass is expressed as an external number, but is expressed in the internal number (% by mass). It is almost the same as the numerical value. The average particle diameters of MnS, MoS, CaF 2 and enstatite powder were 6 μm, 4 μm, 20 μm and 6 μm, respectively.
In addition, as a standard material, 0.8 mass% of zinc stearate as a lubricant was added to the powder of the same iron-based powder, natural graphite powder and copper powder as above, and mixed with a V-type container rotary mixer. Mixed powder was prepared (see Table 1).
次に、得られた各鉄基粉末混合物を、室温下で外径：38mm、内径：25mmの超硬製リング型に充填して加圧成形し、厚さ：８mm、密度：6.9 Mg/m3の成形体としたのち、ＲＸガス中にて、1130℃で20分焼結し、圧環強さ試験用の焼結体とした。
圧環強さは、JIS Z 2507に従い、リング焼結体試験片を直径を挟んで両側から圧縮し、リング試験片が破断したときの圧縮応力を圧環強さとして測定した。
Next, each iron-based powder mixture thus obtained was filled into a carbide ring mold having an outer diameter of 38 mm and an inner diameter of 25 mm at room temperature, and pressure-molded. Thickness: 8 mm, density: 6.9 Mg / m After forming the molded body of No. 3 , it was sintered in RX gas at 1130 ° C. for 20 minutes to obtain a sintered body for the crushing strength test.
The crushing strength was measured in accordance with JIS Z 2507 by compressing the ring sintered body test piece from both sides across the diameter, and measuring the compression stress when the ring test piece was broken as the crushing strength.
さらに、得られた各鉄基粉末混合物を用い、別途、旋盤切削試験用の試験片（外径：60mm，内径：20mm，高さ：20mm）およびドリル切削試験用の試験片（外径：60mm，高さ：20mm）を圧粉成形により作製した。圧粉成形の密度は6.9 Mg/m3とした。また、その後の焼結は上記と同様の条件で行った。
切削性は、表２に示す各材質の切削工具を用いて、旋盤切削試験（切削速度：200m／分、送り：0.1mm／回、切込み深さ：0.5mm）を行い、1000ｍ切削時における切削工具の逃げ面の摩耗幅で評価した。切削工具の逃げ面の摩耗幅が小さいほど、焼結体の切削性が優れているといえる。
また、ドリル切削試験については、ハイス製の直径：３mmのドリルを用いて穿孔試験（ドリル径：３mm、回転数：2500rpm、送り：600mm/min）を行い、ドリルが破損するまでの穿孔数を評価した。
得られた結果を表２に併記する。
Furthermore, using the obtained iron-based powder mixture, separately, a test piece for lathe cutting test (outer diameter: 60 mm, inner diameter: 20 mm, height: 20 mm) and a test piece for drill cutting test (outer diameter: 60 mm) , Height: 20 mm). The density of compacting was 6.9 Mg / m 3 . Further, the subsequent sintering was performed under the same conditions as described above.
Machinability is determined by conducting a lathe cutting test (cutting speed: 200 m / min, feed: 0.1 mm / turn, depth of cut: 0.5 mm) using cutting tools of the various materials shown in Table 2, and cutting at 1000 m. Evaluation was based on the wear width of the flank of the tool. It can be said that the smaller the wear width of the flank of the cutting tool, the better the machinability of the sintered body.
As for the drill cutting test, a drilling test (drill diameter: 3 mm, rotation speed: 2500 rpm, feed: 600 mm / min) using a drill made by Heiss with a diameter of 3 mm is performed to determine the number of drilling holes until the drill breaks. evaluated.
The obtained results are also shown in Table 2.
表２に示した発明例１〜３と比較例１〜４を比較すれば明らかなように、本発明に従う添加材を添加した鉄基粉末混合物を用いて製造した焼結体は、圧環強さの低下はほとんどなく、良好な機械的強度が得られていることが分かる。また、発明例１〜３より、本発明に従う添加材を添加した鉄基粉末混合物を用いて製造した焼結体は、旋盤切削時における工具摩耗が著しく軽減されるだけでなく、ドリル穿孔数も大幅に改善されることが分かる。
これに対し、比較例１，２では、ドリル穿孔数は標準材に比較して著しく改善されたものの、旋盤切削時における工具摩耗の低減は不十分であった。また、比較例３，４では、旋盤切削時の工具摩耗の低減およびドリル穿孔数の改善とも不十分であった。
As is apparent from a comparison between Invention Examples 1 to 3 and Comparative Examples 1 to 4 shown in Table 2, the sintered body produced using the iron-based powder mixture to which the additive according to the present invention was added has a crushing strength. It can be seen that good mechanical strength is obtained. In addition, from Invention Examples 1 to 3, the sintered body manufactured using the iron-based powder mixture to which the additive according to the present invention is added not only significantly reduces tool wear during lathe cutting, but also increases the number of drill holes. It can be seen that it is greatly improved.
On the other hand, in Comparative Examples 1 and 2, although the number of drill holes was remarkably improved as compared with the standard material, the reduction of tool wear during lathe cutting was insufficient. Further, in Comparative Examples 3 and 4, the reduction in tool wear during lathe cutting and the improvement in the number of drill holes were insufficient.
本発明の鉄基粉末混合物を用いることにより、旋盤切削性およびドリル切削性に優れ、また機械的強度が良好な焼結部品を得ることができる。従って、本発明は、例えば自動車用高強度焼結部品等に適用して好適である。 By using the iron-based powder mixture of the present invention, it is possible to obtain a sintered part having excellent lathe cutting performance and drill cutting performance and excellent mechanical strength. Therefore, the present invention is suitable for application to, for example, high-strength sintered parts for automobiles.
Claims (1)
上記MnＳ、MoＳおよびCaF 2 のうちから選んだ少なくとも２種とエンスタタイトの鉄基粉末混合物全体に対する添加量がそれぞれ0.005〜0.995mass％で、かつこれらの合計量が0.01〜1.0mass％で、上記金属石鹸の鉄基粉末混合物全体に対する配合量が0.02〜1.0mass％で、上記合金用粉末の鉄基粉末混合物全体に対する配合量が0.1〜５mass％であることを特徴とする自動車の高強度焼結部品用の鉄基粉末混合物。 At least two kinds selected from MnS, MoS and CaF 2 having an average particle diameter of 1 to 10 μm , 5 to 20 μm and 10 to 50 μm, respectively , as an additive to an iron-based powder having an average particle diameter of 80 to 100 μm ; An iron-based powder mixture in which enstatite having an average particle diameter of 1 to 10 μm is added , and metal soap and alloy powder are further blended,
Addition amount of at least two kinds selected from MnS, MoS and CaF 2 and enstatite to the whole iron-based powder mixture is 0.005 to 0.995 mass%, respectively, and the total amount thereof is 0.01 to 1.0 mass%. High strength sintering of an automobile characterized in that the blending amount of the metal soap with respect to the entire iron-based powder mixture is 0.02 to 1.0 mass%, and the blending amount of the alloy powder with respect to the entire iron-based powder mixture is 0.1 to 5 mass%. Iron-based powder mixture for parts .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2009038553A JP5310074B2 (en) | 2009-02-20 | 2009-02-20 | Iron-based powder mixture for high-strength sintered parts of automobiles |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2009038553A JP5310074B2 (en) | 2009-02-20 | 2009-02-20 | Iron-based powder mixture for high-strength sintered parts of automobiles |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2010189755A JP2010189755A (en) | 2010-09-02 |
| JP5310074B2 true JP5310074B2 (en) | 2013-10-09 |
Family
ID=42816095
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2009038553A Active JP5310074B2 (en) | 2009-02-20 | 2009-02-20 | Iron-based powder mixture for high-strength sintered parts of automobiles |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP5310074B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012144801A (en) * | 2010-02-18 | 2012-08-02 | Jfe Steel Corp | Mixed powder for powder metallurgy and method for producing the same, and sintered body made of iron-based powder excellent in cuttability and method for producing the same |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62167845A (en) * | 1986-01-20 | 1987-07-24 | Kanai Hiroyuki | Manufacture of sintered ring material for spinning machine |
| JP2763826B2 (en) * | 1990-10-18 | 1998-06-11 | 日立粉末冶金株式会社 | Sintered alloy for valve seat |
| JP4323069B2 (en) * | 2000-08-31 | 2009-09-02 | 日立粉末冶金株式会社 | Valve guide material |
| JP4323070B2 (en) * | 2000-08-31 | 2009-09-02 | 日立粉末冶金株式会社 | Valve guide material |
| JP4323071B2 (en) * | 2000-08-31 | 2009-09-02 | 日立粉末冶金株式会社 | Valve guide material |
| JP2004149819A (en) * | 2002-10-29 | 2004-05-27 | Nippon Piston Ring Co Ltd | Ferrous sintered body for valve seat |
| JP4270973B2 (en) * | 2003-07-31 | 2009-06-03 | 日本ピストンリング株式会社 | Iron-based sintered body for valve seats with excellent light metal alloy castability |
-
2009
- 2009-02-20 JP JP2009038553A patent/JP5310074B2/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012144801A (en) * | 2010-02-18 | 2012-08-02 | Jfe Steel Corp | Mixed powder for powder metallurgy and method for producing the same, and sintered body made of iron-based powder excellent in cuttability and method for producing the same |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2010189755A (en) | 2010-09-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4844693B2 (en) | Iron-based powder mixture, iron-based powder molded body, and method for producing iron-based powder sintered body | |
| JP5696512B2 (en) | Mixed powder for powder metallurgy, method for producing the same, iron-based powder sintered body having excellent machinability, and method for producing the same | |
| JP5904234B2 (en) | Mixed powder for powder metallurgy, production method thereof, and sintered body made of iron-based powder | |
| JP2006089829A (en) | Iron-base powdery mixture for powder metallurgy | |
| TWI769130B (en) | Powder metal composition for easy machining | |
| JP5504971B2 (en) | Mixed powder for powder metallurgy and sintered metal powder with excellent machinability | |
| JP5504963B2 (en) | Mixed powder for powder metallurgy and sintered metal powder with excellent machinability | |
| JP5962787B2 (en) | Mixed powder for powder metallurgy, production method thereof, and sintered body made of iron-based powder | |
| JP5741649B2 (en) | Iron-based powder mixture | |
| WO2016190039A1 (en) | Mixed powder for iron-based powder metallurgy and sintered body produced using same | |
| JP5962691B2 (en) | Mixed powder for powder metallurgy, production method thereof, and sintered body made of iron-based powder | |
| JP2009242887A (en) | Iron-based powdery mixture | |
| JP5310074B2 (en) | Iron-based powder mixture for high-strength sintered parts of automobiles | |
| JP5200768B2 (en) | Iron-based mixed powder, and powder molded body and powder sintered body manufacturing method using the same | |
| JP4640162B2 (en) | Iron-based mixed powder for powder metallurgy and iron-based sintered body | |
| JP6380501B2 (en) | Mixed powder for powder metallurgy, method for producing mixed powder for powder metallurgy, and sintered body | |
| JP4935731B2 (en) | Iron-based powder mixture | |
| JP6007928B2 (en) | Mixed powder for powder metallurgy, production method thereof, and sintered body made of iron-based powder | |
| JP2014025109A (en) | Mixed powder for powder metallurgy | |
| JP5504863B2 (en) | Mixed powder for powder metallurgy and sintered metal powder with excellent machinability | |
| JP2018090854A (en) | Mixed powder for iron-based powder metallurgy and method for producing sintered body | |
| JP6493357B2 (en) | Mixed powder for powder metallurgy, method for producing the same, and method for producing a sintered body | |
| JP2017106060A (en) | Mixture powder for powder metallurgy, manufacturing method therefor and manufacturing method of iron-based powder-made sintered body | |
| JP2019127654A (en) | Mixed powder for powder metallurgy | |
| JP2007211329A (en) | Iron-based powdery mixture for powder metallurgy |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20111025 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20130311 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20130319 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20130513 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20130604 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20130617 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 Ref document number: 5310074 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |