Nothing Special   »   [go: up one dir, main page]

JP4948636B2 - Hard particles for blending sintered alloys, wear-resistant iron-based sintered alloys, and valve seats - Google Patents

Hard particles for blending sintered alloys, wear-resistant iron-based sintered alloys, and valve seats Download PDF

Info

Publication number
JP4948636B2
JP4948636B2 JP2010218542A JP2010218542A JP4948636B2 JP 4948636 B2 JP4948636 B2 JP 4948636B2 JP 2010218542 A JP2010218542 A JP 2010218542A JP 2010218542 A JP2010218542 A JP 2010218542A JP 4948636 B2 JP4948636 B2 JP 4948636B2
Authority
JP
Japan
Prior art keywords
hard particles
sintered alloy
wear
valve seat
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
Application number
JP2010218542A
Other languages
Japanese (ja)
Other versions
JP2011190526A (en
Inventor
公彦 安藤
忠義 亀甲
裕作 吉田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fine Sinter Co Ltd
Toyota Motor Corp
Original Assignee
Fine Sinter Co Ltd
Toyota Motor Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Fine Sinter Co Ltd, Toyota Motor Corp filed Critical Fine Sinter Co Ltd
Priority to JP2010218542A priority Critical patent/JP4948636B2/en
Priority to PCT/IB2010/002608 priority patent/WO2011101706A1/en
Priority to CN2010800061575A priority patent/CN102782166A/en
Priority to US13/201,782 priority patent/US20120304821A1/en
Publication of JP2011190526A publication Critical patent/JP2011190526A/en
Application granted granted Critical
Publication of JP4948636B2 publication Critical patent/JP4948636B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C1/00Making non-ferrous alloys
    • C22C1/04Making non-ferrous alloys by powder metallurgy
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C1/00Making non-ferrous alloys
    • C22C1/10Alloys containing non-metals
    • C22C1/1005Pretreatment of the non-metallic additives
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C1/00Making non-ferrous alloys
    • C22C1/10Alloys containing non-metals
    • C22C1/1084Alloys containing non-metals by mechanical alloying (blending, milling)
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C27/00Alloys based on rhenium or a refractory metal not mentioned in groups C22C14/00 or C22C16/00
    • C22C27/04Alloys based on tungsten or molybdenum
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C30/00Alloys containing less than 50% by weight of each constituent
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C33/00Making ferrous alloys
    • C22C33/02Making ferrous alloys by powder metallurgy
    • C22C33/0207Using a mixture of prealloyed powders or a master alloy
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C33/00Making ferrous alloys
    • C22C33/02Making ferrous alloys by powder metallurgy
    • C22C33/0257Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/005Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/04Ferrous alloys, e.g. steel alloys containing manganese
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/44Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/52Ferrous alloys, e.g. steel alloys containing chromium with nickel with cobalt
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2999/00Aspects linked to processes or compositions used in powder metallurgy

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Powder Metallurgy (AREA)

Description

本発明は、焼結合金に配合されるに好適な硬質粒子に係り、特に、焼結合金の耐摩耗性を向上させるに好適な硬質粒子、さらには、これを含有した耐摩耗性鉄基焼結合金、及び該焼結合金で形成されたバルブシートに関する。   The present invention relates to hard particles suitable for blending into a sintered alloy, in particular, hard particles suitable for improving the wear resistance of a sintered alloy, and further, wear-resistant iron-based fired containing the hard particles. The present invention relates to a bonding gold and a valve seat formed of the sintered alloy.

従来から、バルブシートなどには、鉄を基地とした焼結合金が適用されることがある。焼結合金には、耐摩耗性をさらに向上させるべく、硬質粒子を含有させることがある。硬質粒子を含有させる場合、硬質粒子の粉末を、低合金鋼またはステンレス鋼の組成をもつ粉末に混入し、この混合粉末で圧粉成形体を形成し、その後、圧粉成形体を焼結して焼結合金とすることが一般的である。   Conventionally, sintered alloys based on iron may be applied to valve seats and the like. The sintered alloy may contain hard particles in order to further improve the wear resistance. When hard particles are included, powder of hard particles is mixed with powder having a composition of low alloy steel or stainless steel, and a compacted body is formed with this mixed powder, and then the compacted body is sintered. Generally, a sintered alloy is used.

このような硬質粒子として、例えば、質量%でMo:20〜60%、C:0.2〜3%、Ni:5〜40%、Mn:1〜15%、Cr:0.1〜10%を含み、残部が不可避不純物とFeからなる硬質粒子が提案されている(例えば特許文献1参照)。   As such hard particles, for example, by mass: Mo: 20 to 60%, C: 0.2 to 3%, Ni: 5 to 40%, Mn: 1 to 15%, Cr: 0.1 to 10% In other words, hard particles composed of inevitable impurities and Fe have been proposed (see, for example, Patent Document 1).

この硬質粒子を用いて、鉄を基地とした焼結合金を製造した場合には、硬質粒子と母材である鉄基地との密着性を向上できる。さらに、硬質粒子にMoを含むことにより良好なる固体潤滑性を確保することができる。   When a sintered alloy based on iron is produced using these hard particles, the adhesion between the hard particles and the iron base that is the base material can be improved. Furthermore, favorable solid lubricity can be ensured by including Mo in hard particles.

特開2001−181807号公報JP 2001-181807 A

ところで、特許文献1に記載の焼結合金で、内燃機関のバルブシートを製造した場合には、硬質粒子のMoが固体潤滑剤として作用するため、バルブとバルブシートの摺動面の潤滑性を高めることができる。   By the way, when the valve seat of the internal combustion engine is manufactured with the sintered alloy described in Patent Document 1, since the hard particle Mo acts as a solid lubricant, the lubricity of the sliding surface between the valve and the valve seat is improved. Can be increased.

しかしながら、バルブの開閉時には、バルブシートとバルブは、単に相対的に摺動するだけではない。特に、排気側のバルブは、吸気側に比べて高温環境下にあり、この環境下で、バルブの開閉に伴いバルブシートとバルブは間欠的に接触し、この接触時に双方が相対的に摺動するため、接触時の凝着摩耗と、摺動時のアブレッシブ摩耗とが混在(複合)する。このような摩耗形態を厳密に考慮した場合、潤滑性を高めただけでは、バルブシートの耐摩耗性を充分に向上させることができない場合もある。   However, when the valve is opened and closed, the valve seat and the valve do not simply slide relative to each other. In particular, the valve on the exhaust side is in a higher temperature environment than the intake side, and in this environment, the valve seat and the valve are intermittently in contact with the opening and closing of the valve, and at the time of this contact both slide relatively. Therefore, adhesive wear at the time of contact and abrasive wear at the time of sliding are mixed (composite). When such a wear form is strictly considered, the wear resistance of the valve seat may not be sufficiently improved only by improving the lubricity.

本発明は、前記課題を鑑みてなされたものであり、その目的とするところは、高温環境下で、複合した摩耗形態が発現する場合であっても、耐摩耗性を向上させることができる焼結合金配合用硬質粒子、さらには、これを含有した耐摩耗性鉄基焼結合金、及び該焼結合金で形成されたバルブシートを提供することにある。   The present invention has been made in view of the above-described problems, and the object of the present invention is to make it possible to improve wear resistance even when a combined wear form is developed in a high temperature environment. It is another object of the present invention to provide hard particles for bonding gold, an abrasion-resistant iron-based sintered alloy containing the hard particles, and a valve seat formed of the sintered alloy.

発明者らは、前記課題を解決すべく鋭意検討を重ねた結果、これまでの硬質粒子の潤滑特性を維持しつつ、さらに硬質粒子の硬度を高めることが、前記環境下における耐摩耗に有効であると考えた。そして、これを実現する手段として、他の元素と比べて酸化性が高いイットリウム(Y)を硬質粒子に添加することが、この硬質粒子の潤滑特性を確保しつつ、硬質粒子の硬度を高める方法が、最も有効な方法であるとの新たな知見を得た。   As a result of intensive studies to solve the above problems, the inventors have effectively improved the hardness of the hard particles while maintaining the lubrication characteristics of the hard particles so far, which is effective for wear resistance in the environment. I thought it was. And, as a means for realizing this, adding yttrium (Y), which is more oxidizing than other elements, to the hard particles is a method for increasing the hardness of the hard particles while ensuring the lubricating properties of the hard particles. However, we have obtained new knowledge that it is the most effective method.

本発明は、このような新たな知見に基づくものであり、焼結合金配合用硬質粒子は、焼結合金に原料として配合される硬質粒子であって、質量%でMo:20〜40%、C:0.5〜1.0%、Ni:5〜30%、Mn:1〜10%、Cr:1〜10%、Co:5〜30%、Y:0.05〜2%、残部が不可避不純物とFeからなる。なお本明細書では、特に断らない限り、%は質量%(mass%)を意味する。   The present invention is based on such new knowledge, the hard particles for blending sintered alloy is hard particles blended as a raw material in the sintered alloy, Mo: 20-40% in mass%, C: 0.5 to 1.0%, Ni: 5 to 30%, Mn: 1 to 10%, Cr: 1 to 10%, Co: 5 to 30%, Y: 0.05 to 2%, the balance being It consists of inevitable impurities and Fe. In the present specification, unless otherwise specified,% means mass%.

本発明によれば、イットリウムは、大気中において他の元素に比べて極めて酸化し易いので、硬質粒子の成分にY(イットリウム)を添加することにより、硬質粒子には、イットリウムの酸化物(Y)が形成され、この酸化物が硬質粒子内に分散される。これにより、硬質粒子は分散強化され、硬質粒子の硬度を高めることができる。また、イットリウムの酸化物により凝着摩耗も抑制でき、さらに耐摩耗性を向上させることができる。さらに、この硬質粒子を含む焼結合金を切削加工した場合、この焼結合金は、切削工具と凝着され難いため、イットリウムの酸化物により焼結合金の被削性を向上させることができる。 According to the present invention, yttrium is very easy to oxidize in the atmosphere as compared with other elements. Therefore, by adding Y (yttrium) to the hard particle component, the hard particle has an oxide of yttrium (Y 2 O 3 ) is formed and this oxide is dispersed in the hard particles. Thereby, the hard particles are strengthened by dispersion, and the hardness of the hard particles can be increased. Moreover, adhesion wear can be suppressed by the oxide of yttrium, and the wear resistance can be further improved. Further, when the sintered alloy containing hard particles is cut, the sintered alloy is difficult to adhere to the cutting tool, and therefore the machinability of the sintered alloy can be improved by the oxide of yttrium.

ここで、イットリウムを硬質粒子の質量に対して0.05%未満しか添加しない場合には、たとえ硬質粒子内にイットリウムの酸化物(Y)が形成されたとしても、充分に、これを用いた焼結合金の耐摩耗性を期待できるほどの硬度を得ることができない。 Here, when adding less than 0.05% of yttrium to the mass of the hard particles, even if yttrium oxide (Y 2 O 3 ) is formed in the hard particles, this is sufficient. It is not possible to obtain a hardness enough to expect the wear resistance of a sintered alloy using sinter.

一方、イットリウムは、硬質粒子に対して添加をすればするほど、硬質粒子の硬度を高めることができるが、硬質粒子の質量に対して2%を超えて添加した場合には、硬質粒子が脆化してしまい、これを用いて製造した焼結合金の耐摩耗性を低下させることになる。なお、硬質粒子のその他の成分、及びその含有量の技術的意義については、以下の実施形態及び実施例において詳述する。   On the other hand, as yttrium is added to the hard particles, the hardness of the hard particles can be increased. However, when the yttrium is added in excess of 2% with respect to the mass of the hard particles, the hard particles become brittle. As a result, the wear resistance of the sintered alloy produced by using this is reduced. The other components of the hard particles and the technical significance of the content thereof will be described in detail in the following embodiments and examples.

このように構成された焼結合金配合用硬質粒子を用いて、本発明として、耐摩耗性鉄基焼結合金をも開示する。本発明に係る耐摩耗性鉄基焼結合金は、上記焼結合金配合用硬質粒子が分散するように、該焼結合金配合用硬質粒子からなる粉末を基地となる鉄系粉末に混合して、焼結した耐摩耗性鉄基焼結合金であって、前記焼結合金配合用硬質粒子は、前記耐摩耗性鉄基焼結合金に対して、10〜60質量%含有していることがより好ましい。   A wear-resistant iron-based sintered alloy is also disclosed as the present invention using the hard particles for compounding a sintered alloy thus configured. The wear-resistant iron-based sintered alloy according to the present invention is obtained by mixing a powder comprising the sintered alloy compounding hard particles with a base iron-based powder so that the sintered alloy compounding hard particles are dispersed. A sintered wear-resistant iron-based sintered alloy, wherein the hard particles for blending the sintered alloy contain 10 to 60% by mass with respect to the wear-resistant iron-based sintered alloy. More preferred.

本発明によれば、焼結合金は、焼結時に鉄系金属が基地となり、硬質粒子を連結しており、焼結合金に対して硬質粒子が10質量%未満である場合、硬質粒子による耐摩耗性の効果を充分に発揮することができない場合がある。一方、硬質粒子が60質量%を超えた場合、鉄基地の割合が減ってしまい、この結果、硬質粒子を焼結合金に充分な密着力で保持することができない場合がある。これにより、接触・摺動環境など摩耗が発生する環境下では、焼結合金から硬質粒子が脱落してしまい、焼結合金の摩耗が促進されるおそれがある。   According to the present invention, the sintered alloy is based on an iron-based metal at the time of sintering, and hard particles are connected. When the hard particles are less than 10% by mass with respect to the sintered alloy, the sintered alloy has resistance to hard particles. In some cases, the wear effect cannot be fully exhibited. On the other hand, when the amount of hard particles exceeds 60% by mass, the ratio of the iron base decreases, and as a result, the hard particles may not be held with sufficient adhesion to the sintered alloy. As a result, in an environment where wear occurs, such as a contact / sliding environment, the hard particles fall off from the sintered alloy, which may promote wear of the sintered alloy.

さらに、このように構成された耐摩耗性鉄基焼結合金により、バルブシートが形成されることが好ましい。本発明によれば、高温環境下において、上述した接触時の凝着摩耗と、摺動時のアブレッシブ摩耗とが混在した摩耗形態が発現される場合であっても、これまでの硬質粒子の固体潤滑性を損なうことなく、硬質粒子の硬度を高めることができる。これにより、バルブシートの耐摩耗性を、従来のものに比べてより一層向上させることができる。   Furthermore, it is preferable that the valve seat is formed of the wear-resistant iron-based sintered alloy thus configured. According to the present invention, even in a case where a wear form in which the above-described adhesive wear at the time of contact and abrasive wear at the time of sliding are mixed is exhibited in a high temperature environment, the solid particles of the conventional hard particles The hardness of the hard particles can be increased without impairing the lubricity. Thereby, the abrasion resistance of the valve seat can be further improved as compared with the conventional one.

本発明の硬質粒子が配合された焼結合金によれば、高温環境下で、アブレッシブ摩耗と凝着摩耗とが複合した摩耗形態が発現する場合であっても、固体潤滑性と硬度を高めることにより、耐摩耗性をより向上させることができる。   According to the sintered alloy in which the hard particles of the present invention are blended, the solid lubricity and hardness can be improved even in the case where a wear form in which abrasive wear and adhesive wear are combined under high temperature environment. Thus, the wear resistance can be further improved.

実施例1〜4及び比較例1〜3のバルブシートの摩耗試験結果を示した図。The figure which showed the abrasion test result of the valve seat of Examples 1-4 and Comparative Examples 1-3. 実施例5〜10及び比較例4〜15のバルブシートの摩耗試験結果を示した図。The figure which showed the abrasion test result of the valve seat of Examples 5-10 and Comparative Examples 4-15. 実施例11〜15及び比較例16及び17のバルブシートの摩耗試験結果を示した図。The figure which showed the abrasion test result of the valve seat of Examples 11-15 and Comparative Examples 16 and 17. 実施例及び比較例の摩耗試験を説明するための図。The figure for demonstrating the abrasion test of an Example and a comparative example.

以下に、本発明の実施形態を詳述する。本実施形態に係る硬質粒子は、焼結合金に原料として配合される硬質粒子(焼結合金配合用粒子)であり、焼結合金の基地に対して硬度が高い粒子である。硬質粒子は、質量%でMo:20〜40%、C:0.5〜1.0%、Ni:5〜30%、Mn:1〜10%、Cr:1〜10%、Co:5〜30%、Y:0.05〜2%、残部が不可避不純物とFeからなる。   Hereinafter, embodiments of the present invention will be described in detail. The hard particles according to this embodiment are hard particles (sintered alloy compounding particles) blended as a raw material in a sintered alloy, and are particles having a higher hardness than the base of the sintered alloy. Hard particle | grains are Mo: 20-40% by mass%, C: 0.5-1.0%, Ni: 5-30%, Mn: 1-10%, Cr: 1-10%, Co: 5- 30%, Y: 0.05-2%, the balance is inevitable impurities and Fe.

このような硬質粒子は、上述した組成を上述した割合に配合した溶湯を準備し、この溶湯を噴霧化するアトマイズ処理で製造することができる。また、別の方法としては、溶湯を凝固させた凝固体を機械的粉砕で粉末化してもよい。アトマイズ処理としては、ガスアトマイズ処理及び水アトマイズ処理のいずれであってもよいが、焼結性等を考慮すると丸みのある粒子が得られるガスアトマイズ処理がより好ましい。また、ガスアトマイズ処理としては、焼結合金を製造する(焼結する)までにY(イットリウム)を酸化させることができるのであれば、例えば、非酸化性雰囲気(窒素ガスやアルゴンガスなどの不活性ガス雰囲気や真空中)でガスアトマイズ処理してもよい。   Such hard particles can be manufactured by an atomizing process in which a molten metal in which the above-described composition is blended in the above-described ratio is prepared and the molten metal is atomized. As another method, a solidified body obtained by solidifying a molten metal may be pulverized by mechanical pulverization. The atomization process may be either a gas atomization process or a water atomization process, but a gas atomization process that provides round particles is more preferable in consideration of sinterability and the like. Moreover, as a gas atomization process, if it can oxidize Y (yttrium) by manufacturing (sintering) a sintered alloy, it will be, for example, non-oxidizing atmosphere (inert such as nitrogen gas or argon gas) Gas atomization may be performed in a gas atmosphere or in a vacuum.

ここで、上述した硬質粒子の組成の下限値及び上限値としては、後述する組成限定理由、更には、その範囲の中で、硬さ、固体潤滑性、密着性、又はコストなどを考慮して、適用される部材の各特性の重視度合に応じて適宜変更することができる。   Here, as the lower limit value and the upper limit value of the composition of the hard particles described above, the reasons for limiting the composition to be described later, and further, in the range, considering hardness, solid lubricity, adhesion, cost, etc. Depending on the importance of each characteristic of the applied member, it can be changed as appropriate.

まず、硬質粒子の組成のうちMoは、Mo炭化物を形成して硬質粒子の硬さ、耐摩耗性を向上させると共に、固溶しているMoおよびMo炭化物がMo酸化皮膜を形成し、良好なる固体潤滑性を向上させるのに有効である。   First, among the composition of hard particles, Mo forms Mo carbide to improve the hardness and wear resistance of the hard particles, and solid solution of Mo and Mo carbide forms a Mo oxide film and is improved. It is effective for improving the solid lubricity.

Mo量が上記した下限値未満では、硬質粒子における固体潤滑性が不十分となる。上記した上限値を超えると、焼結時において、鉄系基地との密着性が低下する。硬質粒子におけるより好ましいMoの含有量は、21〜39質量%である。   When the amount of Mo is less than the above lower limit value, the solid lubricity in the hard particles becomes insufficient. When the above upper limit is exceeded, the adhesion with the iron-based matrix is reduced during sintering. The more preferable Mo content in the hard particles is 21 to 39% by mass.

硬質粒子の組成のうちCは、Moと結合してMo炭化物を形成し、硬質粒子の硬さ、耐摩耗性を向上させるのに有効である。   Of the composition of the hard particles, C combines with Mo to form Mo carbide, and is effective in improving the hardness and wear resistance of the hard particles.

Cが上記した下限値よりも少なすぎると、耐摩耗性が不十分となり、Cが上記した上限値よりも多すぎると、焼結合金の密度が低下する。硬質粒子におけるより好ましいCの含有量は、0.7〜0.9質量%である。   If C is less than the above lower limit, the wear resistance is insufficient, and if C is more than the above upper limit, the density of the sintered alloy is lowered. The more preferable content of C in the hard particles is 0.7 to 0.9% by mass.

硬質粒子の組成のうちNiは硬質粒子の基地におけるオーステナイトを増加させて、Moの固溶量を増加させ、耐摩耗性を向上させる。また硬質粒子のNiは、焼結合金の基地に拡散して基地おけるオーステナイトを増加させて、Moの固溶量を増加させ、耐摩耗性を向上させるのに有効である。   Of the hard particle composition, Ni increases the austenite at the base of the hard particles, increases the solid solution amount of Mo, and improves the wear resistance. Further, the hard particle Ni is effective for diffusing into the base of the sintered alloy to increase the austenite in the base, increasing the solid solution amount of Mo, and improving the wear resistance.

Niが上記した下限値よりも少なすぎると、Moの固溶量が低下してしまい耐摩耗性が不十分となり、Niが上記した上限値よりも多すぎると、焼結合金の焼き付き易くなり、この結果凝着摩耗がし易くなる。硬質粒子におけるより好ましいNiの含有量は、6〜28質量%である。   If Ni is less than the above lower limit, the solid solution amount of Mo is reduced and wear resistance is insufficient, and if Ni is more than the above upper limit, the sintered alloy is easily seized, As a result, adhesive wear is likely to occur. The more preferable Ni content in the hard particles is 6 to 28% by mass.

硬質粒子の組成のうちMnは、硬質粒子の組成のもとでは、焼結時に硬質粒子から焼結合金の基地へ効率よく拡散するため、硬質粒子と基地との密着性を向上させるのに有効である。更にMnは基地におけるオーステナイト増加作用を期待できる。   Of the hard particle composition, Mn efficiently diffuses from the hard particle to the base of the sintered alloy during sintering under the hard particle composition, which is effective in improving the adhesion between the hard particle and the base. It is. Furthermore, Mn can be expected to increase austenite at the base.

Mnが上記した下限値よりも少なすぎると、基地への拡散する量が少ないため、硬質粒子と基地との密着性が低下し、Moが上記した上限値よりも多すぎると、焼結合金の密度が低下する。硬質粒子におけるより好ましいMnの含有量は、1〜9質量%である。   If Mn is too smaller than the above lower limit, the amount of diffusion to the base is small, so the adhesion between the hard particles and the base is reduced, and if Mo is more than the above upper limit, Density decreases. The more preferable content of Mn in the hard particles is 1 to 9% by mass.

硬質粒子の組成のうちCrは、使用環境温度が高く、硬質粒子における酸化皮膜の生成が多くなる場合、硬質粒子における酸化皮膜の剥離が生じるため、硬質粒子の酸化を抑制するのに有効である。   Of the hard particle composition, Cr is effective in suppressing the oxidation of the hard particles because the use environment temperature is high and when the generation of the oxide film on the hard particles increases, the oxide film peels off the hard particles. .

Crが上記した下限値よりも少なすぎると、硬質粒子における酸化皮膜が厚くなりすぎて、酸化摩耗し易くなり、Crが上記した上限値よりも多すぎると、固体潤滑剤となる酸化皮膜の形成が抑制されてしまう。硬質粒子におけるより好ましいCrの含有量は、2〜9質量%である。   If the Cr is less than the above lower limit, the oxide film on the hard particles becomes too thick and is subject to oxidative wear. If the Cr is more than the above upper limit, formation of an oxide film that becomes a solid lubricant is formed. Will be suppressed. The more preferable content of Cr in the hard particles is 2 to 9% by mass.

硬質粒子の組成のうちCoは、硬質粒子の基地、焼結合金の基地におけるオーステナイトを増加させると共に、硬質粒子の硬さも向上させるのに有効である。   Of the composition of the hard particles, Co is effective for increasing the austenite at the base of the hard particles and the base of the sintered alloy and improving the hardness of the hard particles.

Coが上記した下限値よりも少なすぎると、上述した効果を期待することが難しく、Coが上記した上限値よりも多すぎると、耐摩耗性が低下することがある。硬質粒子におけるより好ましいCoの含有量は、7〜29質量%である。   If Co is less than the above lower limit value, it is difficult to expect the above-described effect, and if Co is more than the above upper limit value, wear resistance may be lowered. The more preferable Co content in the hard particles is 7 to 29% by mass.

硬質粒子の組成のうちYは、大気中において他の元素に比べて極めて酸化し易いので、硬質粒子の成分にYを添加することにより、硬質粒子には、イットリウムの酸化物(Y)が形成され、この酸化物が硬質粒子内に分散され、硬質粒子を強化する。このイットリウムの酸化は、硬質粒子の粉末の製粉時ばかりでなく、成形時、その後、高温環境下で焼結合金として使用時においても発現され得る。さらには、イットリウムの酸化物が焼結合金(硬質粒子)の表面に存在するので、凝着摩耗も抑制でき、耐摩耗性を向上させることができる。 Of the composition of the hard particles, Y is very easy to oxidize in the atmosphere as compared with other elements. Therefore, by adding Y to the hard particle components, the hard particles have yttrium oxide (Y 2 O 3 ) And the oxide is dispersed within the hard particles, strengthening the hard particles. This oxidation of yttrium can be manifested not only during the production of hard particle powders, but also during molding and then when used as a sintered alloy in a high temperature environment. Furthermore, since the oxide of yttrium is present on the surface of the sintered alloy (hard particles), adhesive wear can be suppressed and the wear resistance can be improved.

ここで、Yが上記した下限値よりも少なすぎると、たとえ硬質粒子内にイットリウムの酸化物(Y)が形成されたとしても、充分に、これを用いた焼結合金の耐摩耗性を期待できるほどの硬度を得ることができない。 Here, if Y is less than the above lower limit, even if an oxide of yttrium (Y 2 O 3 ) is formed in the hard particles, the wear resistance of the sintered alloy using this is sufficient. It is not possible to obtain a hardness that can be expected.

一方、イットリウムは、硬質粒子に対して添加をすればするほど、硬質粒子の硬度を高めることができるが、硬質粒子の質量に対して2%を超えて添加した場合には、硬質粒子が脆化され、これを用いて製造した焼結合金の耐摩耗性を低下させることになる。また、この場合には、硬質粒子と基地となる鉄粉粒子とを混合した粉末を成形する際に、硬質粒子の硬度が高くなりすぎてしまうため、成形された圧粉成形体の密度が低くなってしまう。この結果、成形体を焼結した焼結合金の密度は低下してしまい、これにより、焼結合金の耐摩耗性が低下してしまうことになる。   On the other hand, as yttrium is added to the hard particles, the hardness of the hard particles can be increased. However, when the yttrium is added in excess of 2% with respect to the mass of the hard particles, the hard particles become brittle. Therefore, the wear resistance of the sintered alloy produced by using this is reduced. In this case, the hardness of the hard particles becomes too high when molding a powder in which hard particles and base iron powder particles are mixed, so that the density of the molded green compact is low. turn into. As a result, the density of the sintered alloy obtained by sintering the formed body is lowered, and thereby the wear resistance of the sintered alloy is lowered.

硬質粒子の平均粒径としては、鉄基焼結合金の用途、種類などに応じて適宜選択できるが、20〜250μm程度にすることができる。但しこれに限定されるものではない。硬質粒子の硬さは、Yの添加量に依存し、Hv600〜700程度にすることができる。但しこれに限定されるものではなく、要するに、焼結合金の基地などのように硬質粒子の使用対象物に対して硬ければ良い。   The average particle size of the hard particles can be appropriately selected according to the use and type of the iron-based sintered alloy, but can be about 20 to 250 μm. However, it is not limited to this. The hardness of the hard particles depends on the amount of Y added and can be about Hv 600 to 700. However, the present invention is not limited to this. In short, it is only necessary that the hard particles are hard to be used, such as a sintered alloy base.

そして、このような焼結合金配合用の硬質粒子を用いて、上記焼結合金配合用硬質粒子が分散するように、該焼結合金配合用硬質粒子からなる粉末を基地となる鉄系粉末に混合する。この際に、硬質粒子は、混合粉末全体(すなわち耐摩耗性鉄基焼結合金)に対して、10〜60質量%含有していることがより好ましい。   Then, using such hard particles for compounding sintered alloy, the powder composed of the hard particles for compounding sintered alloy is dispersed into a base iron-based powder so that the hard particles for compounding sintered alloy are dispersed. Mix. At this time, the hard particles are more preferably contained in an amount of 10 to 60% by mass with respect to the entire mixed powder (that is, the wear-resistant iron-based sintered alloy).

硬質粒子は、焼結合金の基地に分散し、焼結合金の耐摩耗性を高める硬質相を構成するため、硬質粒子の割合が10質量%未満であると、焼結合金の耐摩耗性は充分でない。硬質粒子の割合60質量%を超えてしまうと、相手攻撃性が高まるばかりでなく、硬質粒子の保持性が確保され難くなる。   Since the hard particles are dispersed in the base of the sintered alloy and constitute a hard phase that enhances the wear resistance of the sintered alloy, if the proportion of hard particles is less than 10% by mass, the wear resistance of the sintered alloy is Not enough. If the ratio of hard particles exceeds 60% by mass, not only the opponent attack property is increased, but also the retention properties of the hard particles are difficult to be secured.

また、混合粉末には、耐摩耗性鉄基焼結合金の基地となる鉄系粉末(例えば純鉄粉末または低合金鋼粉末)を用い、さらにこれに炭素粉末を添加してもよい。低合金鋼粉末はFe−C系粉末を採用することができ、例えば、低合金鋼粉末を100質量%としたとき、C:0.2〜5質量%、残部が不可避不純物とFeからなる組成をもつものを採用することができる。   Further, as the mixed powder, an iron-based powder (for example, pure iron powder or low alloy steel powder) serving as a base of the wear-resistant iron-based sintered alloy may be used, and carbon powder may be further added thereto. The low alloy steel powder can employ Fe-C based powder. For example, when the low alloy steel powder is 100% by mass, C: 0.2 to 5% by mass, and the balance is composed of inevitable impurities and Fe. A thing with can be adopted.

このようにして、得られた混合粉末を、圧粉成形体に成形して、この圧粉成形体を焼結する。焼結温度としては、1050〜1250℃程度、特に、1100〜1150℃程度を採用できる。上記した焼結温度における焼結時間としては、30分〜120分、より好ましくは45〜90分を採用できる。焼結雰囲気としては、不活性ガス雰囲気などの非酸化性雰囲気であってもよく、非酸化性雰囲気としては、窒素雰囲気、アルゴンガス雰囲気、又は真空雰囲気を挙げることができる。   Thus, the obtained mixed powder is shape | molded to a compacting body, and this compacting body is sintered. As a sintering temperature, about 1050 to 1250 ° C., in particular, about 1100 to 1150 ° C. can be adopted. As a sintering time at the above-described sintering temperature, 30 to 120 minutes, more preferably 45 to 90 minutes can be employed. The sintering atmosphere may be a non-oxidizing atmosphere such as an inert gas atmosphere, and examples of the non-oxidizing atmosphere include a nitrogen atmosphere, an argon gas atmosphere, and a vacuum atmosphere.

そして、焼結により得られた鉄基焼結合金の基地は、その硬さを確保するため、パーライトを含む組織を含むことが好ましく、パーライトを含む組織として、パーライト組織、パーライト−オーステナイト系の混合組織、パーライト−フェライト系の混合組織、パーライト−セメンタイト系の混合組織にしてもよい。耐摩耗性を確保するには、硬さが低いフェライトは少ない方が好ましい。基地の硬さは組成にもよるが、Hv120〜300程度であり、熱処理条件、炭素粉末の添加量等により調整できる。但し、硬質粒子と基地との密着性など耐摩耗性を低下させるものでなければ、上記組成及び硬さに限定されるものではない。   The base of the iron-based sintered alloy obtained by sintering preferably contains a structure containing pearlite in order to ensure its hardness. As the structure containing pearlite, a pearlite structure, a mixture of pearlite-austenite The structure may be a pearlite-ferrite mixed structure or a pearlite-cementite mixed structure. In order to ensure wear resistance, it is preferable that the amount of ferrite having low hardness is small. Although the hardness of the base depends on the composition, it is about Hv120 to 300, and can be adjusted by heat treatment conditions, the amount of carbon powder added, and the like. However, the composition and hardness are not limited as long as the wear resistance such as adhesion between the hard particles and the base is not lowered.

そして、耐摩耗性鉄基焼結合金により、内燃機関の排気弁のバルブシートを形成してもよい。内燃機関の排気側のバルブシートの如く、高温環境下において、バルブシートとバルブとの接触時の凝着摩耗と、双方の摺動時のアブレッシブ摩耗とが混在した摩耗形態が発現する場合であっても、これまでの硬質粒子の固体潤滑性を損なうことなく、硬質粒子の硬度を高めることができる。これにより、バルブシートの耐摩耗性を、従来のものに比べてより一層向上させることができる。   And you may form the valve seat of the exhaust valve of an internal combustion engine with an abrasion-resistant iron-based sintered alloy. This is a case where a wear pattern in which adhesion wear at the time of contact between the valve seat and the valve and abrasive wear at the time of sliding occurs in a high temperature environment, such as a valve seat on the exhaust side of an internal combustion engine. However, the hardness of the hard particles can be increased without deteriorating the solid lubricity of the hard particles so far. Thereby, the abrasion resistance of the valve seat can be further improved as compared with the conventional one.

以下に、本発明を具体的に実施した実施例について比較例と共に説明する。
〔実施例1〕
以下に示す方法で、本実施例1に係る硬質粒子を含む焼結合金で形成されたバルブシートを製作した。具体的には、不活性ガス(窒素ガス)を用いたガスアトマイズ処理により、表1に示す組成をもつ溶湯から合金粉末を製造した。これらを44μm〜180μmの範囲に分級し、硬質粒子の粉末とした。この硬質粒子の粉末と、黒鉛粉末と、純鉄粉末とを混合機により混合し、混合材料としての混合粉末を形成した。ここでは、混合粉末に対して硬質粒子の粉末を30質量%とし、黒鉛粉末を0.6質量%とし、残りを純鉄粉末とした。
Below, the example which carried out the present invention concretely is described with a comparative example.
[Example 1]
A valve seat made of a sintered alloy containing hard particles according to Example 1 was manufactured by the method described below. Specifically, alloy powder was produced from a molten metal having the composition shown in Table 1 by gas atomization using an inert gas (nitrogen gas). These were classified into a range of 44 μm to 180 μm to obtain hard particle powder. The hard particle powder, graphite powder, and pure iron powder were mixed by a mixer to form a mixed powder as a mixed material. Here, the hard particle powder was 30% by mass with respect to the mixed powder, the graphite powder was 0.6% by mass, and the rest was pure iron powder.

成形型を用い、上記したように配合した混合粉末を78.4×10Pa(8tonf/cm)の加圧力でリング形状をなす試験片を圧縮成形し、圧粉成形体を形成した。圧粉成形体を1120℃の不活性雰囲気(窒素ガス雰囲気)中で60分間、焼結し、試験片に係る焼結合金(バルブシート)を形成した。 Using a molding die, the mixed powder blended as described above was compression molded into a ring-shaped test piece with a pressure of 78.4 × 10 7 Pa (8 tonf / cm 2 ) to form a green compact. The green compact was sintered in an inert atmosphere (nitrogen gas atmosphere) at 1120 ° C. for 60 minutes to form a sintered alloy (valve seat) according to the test piece.

〔実施例2〜4〕
実施例1と同じようにしてバルブシートを製作した。実施例1と相違する点は、硬質粒子の組成が表1の如くであり、すなわち、バルブシート(焼結合金)の硬質粒子に含有するYを、順次、0.2質量%、1.0質量%、2.0質量%にした点である。
[Examples 2 to 4]
A valve seat was manufactured in the same manner as in Example 1. The difference from Example 1 is that the composition of the hard particles is as shown in Table 1, that is, Y contained in the hard particles of the valve seat (sintered alloy) is successively 0.2 mass%, 1.0. It is the point made into the mass% and 2.0 mass%.

〔比較例1〕
実施例1と同じようにしてバルブシートを製作した。実施例1と相違する点は、硬質粒子の組成が表1の如くであり、すなわち、バルブシート(焼結合金)の硬質粒子の組成を、上述の特許文献1に示す組成及び含有量にした点である。
[Comparative Example 1]
A valve seat was manufactured in the same manner as in Example 1. The difference from Example 1 is that the composition of the hard particles is as shown in Table 1, that is, the composition of the hard particles of the valve seat (sintered alloy) is set to the composition and content shown in Patent Document 1 described above. Is a point.

〔比較例2〕
実施例1と同じようにしてバルブシートを製作した。実施例1と相違する点は、硬質粒子の組成が表1の如くであり、すなわち、バルブシート(焼結合金)の硬質粒子に含有するYを、0質量%にした(含有しなかった)点である。
[Comparative Example 2]
A valve seat was manufactured in the same manner as in Example 1. The difference from Example 1 is that the composition of the hard particles is as shown in Table 1, that is, Y contained in the hard particles of the valve seat (sintered alloy) was 0 mass% (not contained). Is a point.

〔比較例3〕
実施例1と同じようにしてバルブシートを製作した。実施例1と相違する点は、硬質粒子の組成が表1の如くであり、すなわち、バルブシート(焼結合金)の硬質粒子に含有するYを、5.0質量%にした点である。
[Comparative Example 3]
A valve seat was manufactured in the same manner as in Example 1. The difference from Example 1 is that the composition of the hard particles is as shown in Table 1, that is, the Y contained in the hard particles of the valve seat (sintered alloy) is 5.0% by mass.

Figure 0004948636
Figure 0004948636

<摩耗試験>
次に、図4の試験機を用い焼結合金の耐摩耗性について摩耗試験を行い、耐摩耗性を評価した。この摩耗試験では、図4に示すように、プロパンガスバーナ10を加熱源として用い、前記のように作製した焼結合金からなるリング形状のバルブシート12と、バルブ13のバルブフェース14との摺動部をプロパンガス燃焼雰囲気とした。バルブフェース14はSUH11に軟窒化処理を行ったものである。バルブシート12の温度を200℃に制御し、スプリング16によりバルブシート12とバルブフェース14との接触時に18kgfの荷重を付与して、2000回/分の割合で、バルブシート12とバルブフェース14とを接触させ、8時間の摩耗試験を行った。
<Abrasion test>
Next, a wear test was performed on the wear resistance of the sintered alloy using the testing machine shown in FIG. 4 to evaluate the wear resistance. In this wear test, as shown in FIG. 4, the propane gas burner 10 is used as a heating source, and the ring-shaped valve seat 12 made of a sintered alloy produced as described above and the valve face 14 of the valve 13 slide. The part was a propane gas combustion atmosphere. The valve face 14 is obtained by soft nitriding the SUH 11. The temperature of the valve seat 12 is controlled to 200 ° C., a load of 18 kgf is applied by the spring 16 when the valve seat 12 and the valve face 14 are in contact, and the valve seat 12 and the valve face 14 are And an abrasion test for 8 hours was conducted.

このときのバルブシートの摩耗量(摩耗深さ)を測定した。この結果を図1に示す。なお、図1に示す摩耗量比は、比較例1のバルブシートの摩耗量を1として正規化したものである。   The amount of wear (wear depth) of the valve seat at this time was measured. The result is shown in FIG. The wear amount ratio shown in FIG. 1 is normalized by assuming the wear amount of the valve seat of Comparative Example 1 to be 1.

<硬さ試験>
実施例2〜4及び比較例2にかかる硬質粒子の硬さを測定荷重0.1kgfのマイクロビッカース硬度計を用いて測定した。この結果を以下の表2に示す。
<Hardness test>
The hardness of the hard particles according to Examples 2 to 4 and Comparative Example 2 was measured using a micro Vickers hardness meter with a measurement load of 0.1 kgf. The results are shown in Table 2 below.

Figure 0004948636
Figure 0004948636

<結果1>
図1に示すように、実施例1〜4のバルブシートの摩耗量比は、比較例1〜3のものに比べて小さかった。表2に示すように、硬質粒子の硬さは、硬質粒子のYの含有量(添加量)の増加と共に大きくなり、硬さの上昇率は、硬質粒子のYの含有量(添加量)の増加と共に低下した。
<Result 1>
As shown in FIG. 1, the wear amount ratios of the valve seats of Examples 1 to 4 were smaller than those of Comparative Examples 1 to 3. As shown in Table 2, the hardness of the hard particles increases with an increase in the Y content (addition amount) of the hard particles, and the rate of increase in hardness is the Y content (addition amount) of the hard particles. It declined with the increase.

<評価1>
結果1より、硬質粒子にYを添加することにより、硬質粒子の硬度が上昇し、この結果、バルブシートの耐摩耗性が向上することがわかる。これは、Yの酸化物(Y)が硬質粒子に微細に分散し、これにより硬質粒子が強化されたからであると考えられる。そして、Yの含有量が0.2質量%未満の場合には、Yの酸化物による強化が充分でない場合があり、2質量%を超えた場合には、硬質粒子の脆化により充分な耐摩耗性が得られないと考えられる。
<Evaluation 1>
From the result 1, it can be seen that by adding Y to the hard particles, the hardness of the hard particles is increased, and as a result, the wear resistance of the valve seat is improved. This is presumably because the oxide of Y (Y 2 O 3 ) was finely dispersed in the hard particles, thereby strengthening the hard particles. When the Y content is less than 0.2% by mass, strengthening by the oxide of Y may not be sufficient, and when it exceeds 2% by mass, sufficient resistance is obtained due to embrittlement of the hard particles. Abrasion is not expected.

〔実施例5〜10〕
実施例1と同じようにしてバルブシートを製作した。実施例1と相違する点は、硬質粒子の各組成の含有量である。具体的には、表2に示すように、硬質粒子を、質量%でMo:20〜40%、C:0.5〜1.0%、Ni:5〜30%、Mn:1〜10%、Cr:1〜10%、Co:5〜30%、Y:0.05〜2%、の範囲に収まるように、硬質粒子が含有する各組成の量を調整した点である。
[Examples 5 to 10]
A valve seat was manufactured in the same manner as in Example 1. The difference from Example 1 is the content of each composition of hard particles. Specifically, as shown in Table 2, the hard particles are, in mass%, Mo: 20 to 40%, C: 0.5 to 1.0%, Ni: 5 to 30%, Mn: 1 to 10%. , Cr: 1 to 10%, Co: 5 to 30%, and Y: 0.05 to 2%. The amount of each composition contained in the hard particles is adjusted.

〔比較例4〜15〕
実施例1と同じようにしてバルブシートを製作した。実施例1と相違する点は、表3に示すように、硬質粒子が含有する各組成の量である。具体的には、比較例4及び5の硬質粒子は、本発明の組成のうち、Moのみの含有量が、Mo:20〜40%の範囲から外れるようにした。比較例6及び7の硬質粒子は、本発明の組成のうち、Cのみの含有量が、C:0.5〜1.0%の範囲から外れるようにした。比較例8及び9の硬質粒子は、本発明の組成のうち、Niのみの含有量が、Ni:5〜30%の範囲から外れるようにした。比較例10及び11の硬質粒子は、本発明の組成のうち、Mnのみの含有量が、Mn:1〜10%の範囲から外れるようにした。比較例12及び13の硬質粒子は、本発明の組成のうち、Crのみの含有量が、Cr:1〜10%の範囲から外れるようにした。比較例14及び15の硬質粒子は、本発明の組成のうち、Coのみの含有量が、Co:5〜30%の範囲から外れるようにした。
[Comparative Examples 4 to 15]
A valve seat was manufactured in the same manner as in Example 1. The difference from Example 1 is the amount of each composition contained in the hard particles, as shown in Table 3. Specifically, in the hard particles of Comparative Examples 4 and 5, in the composition of the present invention, the content of only Mo was out of the range of Mo: 20 to 40%. In the hard particles of Comparative Examples 6 and 7, in the composition of the present invention, the content of only C was out of the range of C: 0.5 to 1.0%. The hard particles of Comparative Examples 8 and 9 were such that the content of only Ni out of the composition of the present invention was out of the range of Ni: 5 to 30%. The hard particles of Comparative Examples 10 and 11 were such that the content of only Mn out of the composition of the present invention was out of the range of Mn: 1 to 10%. The hard particles of Comparative Examples 12 and 13 were such that the content of only Cr out of the composition of the present invention was out of the range of Cr: 1 to 10%. The hard particles of Comparative Examples 14 and 15 were such that the content of only Co in the composition of the present invention was out of the range of Co: 5 to 30%.

Figure 0004948636
Figure 0004948636

<摩耗試験>
実施例5〜10のバルブシート及び比較例4〜15のバルブシートに対して、実施例1のバルブシートの摩耗試験と同様の摩耗試験を行った。この結果を、図2に示す。なお、図2に示す摩耗量比は、比較例1のバルブシートの摩耗量を1として正規化したものであり、図2には比較例1のバルブシートの摩耗量比も合わせて示した。
<Abrasion test>
A wear test similar to the wear test of the valve seat of Example 1 was performed on the valve seats of Examples 5 to 10 and the valve seats of Comparative Examples 4 to 15. The result is shown in FIG. The wear amount ratio shown in FIG. 2 is normalized by setting the wear amount of the valve seat of Comparative Example 1 to 1. FIG. 2 also shows the wear amount ratio of the valve seat of Comparative Example 1.

<結果2>
図2に示すように、実施例5〜10のバルブシートの摩耗量比は、比較例4〜15のものに比べて、小さかった。
<Result 2>
As shown in FIG. 2, the wear amount ratio of the valve seats of Examples 5 to 10 was smaller than those of Comparative Examples 4 to 15.

<評価2>
結果2より、硬質粒子を、質量%でMo:20〜40%、C:0.5〜1.0%、Ni:5〜30%、Mn:1〜10%、Cr:1〜10%、Co:5〜30%、Y:0.05〜2%、の範囲に収まるように、硬質粒子が含有する各組成の量を調整することにより、バルブシートの摩耗量が低減されたといえる。
<Evaluation 2>
From the result 2, hard particles are, in mass%, Mo: 20 to 40%, C: 0.5 to 1.0%, Ni: 5 to 30%, Mn: 1 to 10%, Cr: 1 to 10%, It can be said that the wear amount of the valve seat was reduced by adjusting the amount of each composition contained in the hard particles so as to fall within the ranges of Co: 5 to 30% and Y: 0.05 to 2%.

〔実施例11〜15〕
実施例2と同じようにしてバルブシートを製作した。実施例2と相違する点は、混合粉末に対して硬質粒子の粉末を、以下の表4に示すように順次、10質量%,20質量%,30質量%、50質量%、60質量%とし、黒鉛粉末は実施例2と同量、添加した点である。
[Examples 11 to 15]
A valve seat was manufactured in the same manner as in Example 2. The difference from Example 2 is that, as shown in Table 4 below, the hard particle powder is successively 10% by mass, 20% by mass, 30% by mass, 50% by mass, and 60% by mass with respect to the mixed powder. The graphite powder was added in the same amount as in Example 2.

〔比較例16及び17〕
実施例2と同じようにしてバルブシートを製作した。実施例2と相違する点は、混合粉末に対して硬質粒子の粉末を、以下の表4に示すように順次、5質量%,70質量%とし、黒鉛粉末は実施例2と同量、添加した点である。
[Comparative Examples 16 and 17]
A valve seat was manufactured in the same manner as in Example 2. The difference from Example 2 is that the powder of hard particles is sequentially 5% by mass and 70% by mass as shown in Table 4 below with respect to the mixed powder, and the same amount of graphite powder is added as in Example 2. This is the point.

<摩耗試験>
実施例11〜15のバルブシート及び比較例16及び17のバルブシートに対して、実施例1のバルブシートの摩耗試験と同様の摩耗試験を行った。この結果を、図3に示す。なお、図3に示す摩耗量比は、比較例1のバルブシートの摩耗量を1として正規化したものであり、比較例1のバルブシートの摩耗量比も合わせて示した。
<Abrasion test>
A wear test similar to the wear test of the valve seat of Example 1 was performed on the valve seats of Examples 11 to 15 and the valve seats of Comparative Examples 16 and 17. The result is shown in FIG. The wear amount ratio shown in FIG. 3 is normalized with the wear amount of the valve seat of Comparative Example 1 being 1, and the wear amount ratio of the valve seat of Comparative Example 1 is also shown.

Figure 0004948636
Figure 0004948636

<結果2>
図3に示すように、実施例11〜15のバルブシートの摩耗量比は、比較例16及び17のものに比べて、小さかった。
<Result 2>
As shown in FIG. 3, the wear amount ratio of the valve seats of Examples 11 to 15 was smaller than those of Comparative Examples 16 and 17.

<評価2>
結果2より、焼結合金配合用硬質粒子は、前記耐摩耗性鉄基焼結合金に対して、10〜60質量%含有していることが好ましく、この範囲から外れて小さい場合には、硬質粒子による耐摩耗性の効果を充分に発揮することができず、この範囲から外れて大きい場合には、鉄基地の割合が減ってしまい、この結果、硬質粒子を焼結合金に充分に密着することができないと考えられる。
<Evaluation 2>
From the results 2, it is preferable that the hard particles for blending sintered alloy is contained in an amount of 10 to 60% by mass with respect to the wear-resistant iron-based sintered alloy. If the effect of the wear resistance by the particles cannot be sufficiently exhibited, and the ratio is large outside this range, the ratio of the iron base is reduced, and as a result, the hard particles are sufficiently adhered to the sintered alloy. It is considered impossible.

以上、本発明の実施形態について詳述したが、本発明は、前記の実施形態に限定されるものではなく、特許請求の範囲に記載された本発明の精神を逸脱しない範囲で、種々の設計変更を行うことができるものである。   Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various designs can be made without departing from the spirit of the present invention described in the claims. It can be changed.

高温の使用環境下となる、圧縮天然ガスや液化石油ガス、ガソリンを燃料とするエンジンのバルブ系(例えばバルブシート、バルブガイド)に好適に用いることができる。   It can be suitably used for a valve system (for example, a valve seat, a valve guide) of an engine that uses compressed natural gas, liquefied petroleum gas, or gasoline as fuel under a high temperature use environment.

Claims (3)

焼結合金に原料として配合される硬質粒子であって、質量%でMo:20〜40%、C:0.5〜1.0%、Ni:5〜30%、Mn:1〜10%、Cr:1〜10%、Co:5〜30%、Y:0.05〜2%、残部が不可避不純物とFeとからなることを特徴とする焼結合金配合用硬質粒子。   Hard particles blended as a raw material in the sintered alloy, and in mass% Mo: 20-40%, C: 0.5-1.0%, Ni: 5-30%, Mn: 1-10%, Hard particles for blending sintered alloy, characterized in that Cr: 1 to 10%, Co: 5 to 30%, Y: 0.05 to 2%, and the balance consisting of inevitable impurities and Fe. 請求項1に記載の焼結合金配合用硬質粒子が分散するように、該焼結合金配合用硬質粒子からなる粉末を基地となる鉄系粉末に混合して、焼結した耐摩耗性鉄基焼結合金であって、
前記焼結合金配合用硬質粒子は、前記耐摩耗性鉄基焼結合金に対して、10〜60質量%含有していることを特徴とする耐摩耗性鉄基焼結合金。
A powder comprising the sintered alloy compounding hard particles is mixed with a base iron-based powder so as to disperse the sintered alloy compounding hard particles according to claim 1 and sintered, and then the wear-resistant iron group is sintered. A sintered alloy,
10. The wear resistant iron-based sintered alloy, wherein the hard particles for blending the sintered alloy are contained in an amount of 10 to 60% by mass with respect to the wear-resistant iron-based sintered alloy.
請求項2に記載の耐摩耗性鉄基焼結合金で形成されていることを特徴とするバルブシート。   A valve seat formed of the wear-resistant iron-based sintered alloy according to claim 2.
JP2010218542A 2010-02-19 2010-09-29 Hard particles for blending sintered alloys, wear-resistant iron-based sintered alloys, and valve seats Active JP4948636B2 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
JP2010218542A JP4948636B2 (en) 2010-02-19 2010-09-29 Hard particles for blending sintered alloys, wear-resistant iron-based sintered alloys, and valve seats
PCT/IB2010/002608 WO2011101706A1 (en) 2010-02-19 2010-10-13 Hard particles for blending in sintered alloy, wear-resistant iron-based sintered alloy containing hard particles, valve seat formed of sintered alloy, and process for manufacturing hard particles
CN2010800061575A CN102782166A (en) 2010-02-19 2010-10-13 Hard particles for blending in sintered alloy, wear-resistant iron-based sintered alloy containing hard particles, valve seat formed of sintered alloy, and process for manufacturing hard particles
US13/201,782 US20120304821A1 (en) 2010-02-19 2010-10-13 Hard particles for blending in sintered alloy, wear-resistant iron-based sintered alloy containing hard particles, valve seat formed of sintered alloy, and process for manufacturing hard particles

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2010034307 2010-02-19
JP2010034307 2010-02-19
JP2010218542A JP4948636B2 (en) 2010-02-19 2010-09-29 Hard particles for blending sintered alloys, wear-resistant iron-based sintered alloys, and valve seats

Publications (2)

Publication Number Publication Date
JP2011190526A JP2011190526A (en) 2011-09-29
JP4948636B2 true JP4948636B2 (en) 2012-06-06

Family

ID=43477942

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2010218542A Active JP4948636B2 (en) 2010-02-19 2010-09-29 Hard particles for blending sintered alloys, wear-resistant iron-based sintered alloys, and valve seats

Country Status (4)

Country Link
US (1) US20120304821A1 (en)
JP (1) JP4948636B2 (en)
CN (1) CN102782166A (en)
WO (1) WO2011101706A1 (en)

Families Citing this family (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102012202859A1 (en) * 2012-02-24 2013-08-29 Mahle International Gmbh Valve system for charge exchange control
JP5637201B2 (en) 2012-11-14 2014-12-10 トヨタ自動車株式会社 Hard particles for blending sintered alloy, wear-resistant iron-based sintered alloy, and method for producing the same
BR102013021206A2 (en) * 2012-12-11 2014-09-09 Wärtsilä Schweiz AG GAS EXCHANGE VALVE AS WELL AS METHOD FOR MANUFACTURING GAS EXCHANGE VALVE
CN103266249B (en) * 2013-05-24 2015-08-05 成都工业学院 The drilling bit of a kind of vanadium carbide titanium Wimet and preparation thereof and preparation method
JP6595223B2 (en) * 2015-06-22 2019-10-23 株式会社ファインシンター Alloy powder for matrix composition of sintered alloy, sintered alloy containing alloy powder for matrix composition, and method for producing sintered alloy
JP7156193B2 (en) 2019-07-12 2022-10-19 トヨタ自動車株式会社 Hard particles and sintered sliding member using the same
US11353117B1 (en) 2020-01-17 2022-06-07 Vulcan Industrial Holdings, LLC Valve seat insert system and method
US11421679B1 (en) 2020-06-30 2022-08-23 Vulcan Industrial Holdings, LLC Packing assembly with threaded sleeve for interaction with an installation tool
US11421680B1 (en) 2020-06-30 2022-08-23 Vulcan Industrial Holdings, LLC Packing bore wear sleeve retainer system
US12049889B2 (en) 2020-06-30 2024-07-30 Vulcan Industrial Holdings, LLC Packing bore wear sleeve retainer system
US11384756B1 (en) 2020-08-19 2022-07-12 Vulcan Industrial Holdings, LLC Composite valve seat system and method
USD997992S1 (en) 2020-08-21 2023-09-05 Vulcan Industrial Holdings, LLC Fluid end for a pumping system
USD980876S1 (en) 2020-08-21 2023-03-14 Vulcan Industrial Holdings, LLC Fluid end for a pumping system
USD986928S1 (en) 2020-08-21 2023-05-23 Vulcan Industrial Holdings, LLC Fluid end for a pumping system
JP7453118B2 (en) * 2020-10-12 2024-03-19 トヨタ自動車株式会社 Method for manufacturing hard particles, sliding members, and sintered alloys
US11391374B1 (en) 2021-01-14 2022-07-19 Vulcan Industrial Holdings, LLC Dual ring stuffing box
US12055221B2 (en) 2021-01-14 2024-08-06 Vulcan Industrial Holdings, LLC Dual ring stuffing box
US11434900B1 (en) * 2022-04-25 2022-09-06 Vulcan Industrial Holdings, LLC Spring controlling valve
US11920684B1 (en) 2022-05-17 2024-03-05 Vulcan Industrial Holdings, LLC Mechanically or hybrid mounted valve seat

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE654829C (en) * 1930-02-15 1937-12-31 Wilhelm Mueller Dr Hard metal alloy
JPH0753900B2 (en) * 1986-10-27 1995-06-07 日産自動車株式会社 Heat and wear resistant iron-based sintered alloy
JP3596751B2 (en) * 1999-12-17 2004-12-02 トヨタ自動車株式会社 Hard particle for blending sintered alloy, wear-resistant iron-based sintered alloy, method for producing wear-resistant iron-based sintered alloy, and valve seat
JP4624600B2 (en) * 2001-06-08 2011-02-02 トヨタ自動車株式会社 Sintered alloy, manufacturing method thereof and valve seat
JP3763782B2 (en) * 2001-12-28 2006-04-05 日本ピストンリング株式会社 Method for producing wear-resistant iron-based sintered alloy material for valve seat
JP5125488B2 (en) * 2007-12-26 2013-01-23 大同特殊鋼株式会社 Hard particle powder for sintered body and sintered body
JP2011157617A (en) * 2010-02-04 2011-08-18 Daido Steel Co Ltd Hard particle for sintered compact, and the sintered compact

Also Published As

Publication number Publication date
US20120304821A1 (en) 2012-12-06
JP2011190526A (en) 2011-09-29
CN102782166A (en) 2012-11-14
WO2011101706A1 (en) 2011-08-25

Similar Documents

Publication Publication Date Title
JP4948636B2 (en) Hard particles for blending sintered alloys, wear-resistant iron-based sintered alloys, and valve seats
JP4127021B2 (en) Hard particles, wear-resistant iron-based sintered alloy, method for producing wear-resistant iron-based sintered alloy, and valve seat
JP3596751B2 (en) Hard particle for blending sintered alloy, wear-resistant iron-based sintered alloy, method for producing wear-resistant iron-based sintered alloy, and valve seat
JP4368245B2 (en) Hard particle dispersion type iron-based sintered alloy
JP4624600B2 (en) Sintered alloy, manufacturing method thereof and valve seat
JP5637201B2 (en) Hard particles for blending sintered alloy, wear-resistant iron-based sintered alloy, and method for producing the same
JP2004124162A (en) Manufacturing method of iron-based sintered alloy valve seat exhibiting wear resistance under high surface pressure applied condition
KR20130030505A (en) Valve seat of engine and manufacturing method therof
JP4693170B2 (en) Wear-resistant sintered alloy and method for producing the same
JP2004307950A (en) Iron-based sintered alloy, valve seat ring, raw material powder for producing iron-based sintered alloy and method of producing iron-based sintered alloy
JP6431012B2 (en) Method for producing wear-resistant iron-based sintered alloy and wear-resistant iron-based sintered alloy
JP6392796B2 (en) Method for producing wear-resistant iron-based sintered alloy, compact for sintered alloy, and wear-resistant iron-based sintered alloy
JP6077499B2 (en) Sintered alloy molded body, wear-resistant iron-based sintered alloy, and method for producing the same
JP2017137535A (en) Manufacturing method of abrasion resistant iron-based sintered alloy, molded article for sintered alloy and abrasion resistant iron-based sintered alloy
JP2001158934A (en) Method for producing wear resistant ferrous sintered alloy
JP3942136B2 (en) Iron-based sintered alloy
JPS63109142A (en) Ferrous sintered alloy combining heat resistance with wear resistance
JP7156193B2 (en) Hard particles and sintered sliding member using the same
JP2018178143A (en) Manufacturing method of abrasion resistant iron-based sintered alloy
JPH0533299B2 (en)
JP2006274359A (en) Alloy powder for forming hard phase and ferrous powder mixture using the same
JPH11302805A (en) Sintered valve seat and its production
JP2000054088A (en) High strength iron-base sintered valve seat
JPS63203754A (en) Sintered iron alloy having wear resistance at high temperature
JPH06101427A (en) Iron group sintered alloy made valve seat for internal combustion engine

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20110704

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20120209

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: 20120214

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20120306

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20150316

Year of fee payment: 3

R151 Written notification of patent or utility model registration

Ref document number: 4948636

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R151

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20150316

Year of fee payment: 3

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20150316

Year of fee payment: 3

R154 Certificate of patent or utility model (reissue)

Free format text: JAPANESE INTERMEDIATE CODE: R154

S111 Request for change of ownership or part of ownership

Free format text: JAPANESE INTERMEDIATE CODE: R313114

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20150316

Year of fee payment: 3

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

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

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

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

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250