JP3264092B2 - Wear-resistant iron-based sintered alloy and method for producing the same - Google Patents

Wear-resistant iron-based sintered alloy and method for producing the same

Info

Publication number
JP3264092B2
JP3264092B2 JP11797094A JP11797094A JP3264092B2 JP 3264092 B2 JP3264092 B2 JP 3264092B2 JP 11797094 A JP11797094 A JP 11797094A JP 11797094 A JP11797094 A JP 11797094A JP 3264092 B2 JP3264092 B2 JP 3264092B2
Authority
JP
Japan
Prior art keywords
iron
sintered
alloy
powder
alloy powder
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP11797094A
Other languages
Japanese (ja)
Other versions
JPH07138714A (en
Inventor
義孝 高橋
忠孝 金子
攝人 台座
与志彦 伊藤
Original Assignee
トヨタ自動車株式会社
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
Priority to JP23844993 priority Critical
Priority to JP5-238449 priority
Application filed by トヨタ自動車株式会社 filed Critical トヨタ自動車株式会社
Priority to JP11797094A priority patent/JP3264092B2/en
Publication of JPH07138714A publication Critical patent/JPH07138714A/en
Application granted granted Critical
Publication of JP3264092B2 publication Critical patent/JP3264092B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION
【0001】[0001]
【産業上の利用分野】本発明は耐摩耗性に優れた鉄基焼
結合金とその製造方法に関する。本発明は、例えば、自
動車等の車両の内燃機関に使用されるバルブシート、ピ
ストンリング或いは排気系のカラー等の焼結部品に有用
である。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an iron-based sintered alloy having excellent wear resistance and a method for producing the same. INDUSTRIAL APPLICABILITY The present invention is useful for sintered parts such as valve seats, piston rings, and exhaust system collars used in internal combustion engines of vehicles such as automobiles.
【0002】[0002]
【従来の技術】耐摩耗性をもつ鉄基焼結合金の従来技術
について、自動車の内燃機関に使用されるバルブシート
用焼結合金を例にとって説明する。従来より、バルブシ
ート用焼結合金としては、Fe−C−Co−Ni基材
料、Fe−C基材料に耐摩耗性の向上を狙ってフェロモ
リブデン(Fe−Mo)、フェロクロム(Fe−Cr)
等の金属間化合物またはFe−C−Cr−Mo−V合金
等を添加したものが使用されている(特開昭56−15
4110号公報)。
2. Description of the Related Art Conventional iron-based sintered alloys having wear resistance will be described with reference to sintered alloys for valve seats used in internal combustion engines of automobiles. Conventionally, ferromolybdenum (Fe-Mo) and ferrochrome (Fe-Cr) have been used as sintered alloys for valve seats in order to improve wear resistance of Fe-C-Co-Ni-based materials and Fe-C-based materials.
And the like to which an intermetallic compound such as Fe-C-Cr-Mo-V alloy is added (JP-A-56-15).
No. 4110).
【0003】さらに、CrおよびMoを含有するFe−
C基地組織中に、Cr、Mo、V等からなる鉄系硬質粒
子を分散させ耐摩耗性と相手攻撃性を改善した焼結合金
(特開昭60−224762号公報)、またFe−C−
Co−Ni系基地組織中にFeMoおよびFeWからな
る硬質粒子を分散させさらにPb合金等を含浸させて耐
摩耗性を改善した焼結合金(特開昭62−202058
号公報)が開示されている。
Further, Fe— containing Cr and Mo
A sintered alloy in which iron-based hard particles composed of Cr, Mo, V, etc. are dispersed in a C base structure to improve abrasion resistance and aggressiveness to a partner (Japanese Patent Laid-Open No. 60-224762), and Fe-C-
A sintered alloy in which hard particles made of FeMo and FeW are dispersed in a Co-Ni base matrix and impregnated with a Pb alloy or the like to improve wear resistance (Japanese Patent Laid-Open No. 62-202058)
Gazette).
【0004】バルブシート材に要求される特性として
は、耐摩耗性の他に耐腐食性および耐熱性が挙げられ
る。ここで耐摩耗性は主として硬質粒子が受持ち、耐腐
食性および耐熱性は主として基地組織が受持ち、両者が
相まって耐久性を確保している。
The characteristics required of the valve seat material include corrosion resistance and heat resistance in addition to wear resistance. Here, the hard particles are mainly responsible for the wear resistance, and the corrosion resistance and heat resistance are mainly responsible for the base structure, and both of them ensure durability.
【0005】[0005]
【発明が解決しようとする課題】ところで最近、耐摩耗
性鉄基焼結合金を用いる分野においてはその焼結合金の
性質の改善要求が一段と高まっている。例えば、自動車
の内燃機関においては、長寿命化、高出力、高回転化、
排出ガス浄化対策、あるいは燃費向上対策に対する改善
要求が一段と高まっており、このため、自動車の内燃機
関におけるエンジンバルブ、バルブシートに対しては、
従来にも増して厳しい使用環境に耐えることが不可避と
なってきており、耐熱性、耐摩耗性をより一層向上させ
ると共に、高温での耐腐食性を向上させる必要が生じて
きている。
In recent years, in the field of using a wear-resistant iron-based sintered alloy, there is an increasing demand for improving the properties of the sintered alloy. For example, in internal combustion engines of automobiles, longer life, higher output, higher rotation,
There is a growing demand for improvements in exhaust gas purification measures or fuel economy improvement measures. For this reason, engine valves and valve seats in internal combustion engines of automobiles have
It has become unavoidable to withstand harsh use environments more than ever before, and it has become necessary to further improve heat resistance and abrasion resistance and to improve corrosion resistance at high temperatures.
【0006】しかるに、従来より提供されている鉄系バ
ルブシート材の基地の形成は、鉄粉末に対して、合金元
素であるNi粉末、Co粉末、Mo粉末等のそれぞれの
元素の要素粉末を混合した混合粉末を用い、この混合粉
末を原料として圧粉体を成形し、圧粉体を焼結して焼結
体を形成し、これによりNi、Co、Mo等を鉄中に拡
散させている。そのため、これら合金元素を鉄中に完全
に拡散させることが難しく、合金添加量に見合った特性
の向上が得られにくい。
[0006] However, the base of the iron-based valve seat material conventionally provided is formed by mixing the element powder of each element such as Ni powder, Co powder, and Mo powder, which are alloying elements, with iron powder. Using this mixed powder, a green compact is formed using the mixed powder as a raw material, and the green compact is sintered to form a sintered body, whereby Ni, Co, Mo, and the like are diffused into iron. . Therefore, it is difficult to completely diffuse these alloy elements into iron, and it is difficult to obtain an improvement in characteristics corresponding to the amount of alloy added.
【0007】そこで、合金元素添加の効果を効率良く引
き出すために、合金元素を予め鉄と合金化した粉末を採
用することが考えられるが、これら合金元素を鉄と予め
合金化した粉末では、固溶硬化により粉末の圧縮性が低
下するため、圧粉体の高密度化が難しくなり、強度及び
耐久性向上に対し不利に作用する。本発明は上記した従
来の鉄基焼結合金における問題点を解決すべくなされた
ものである。請求項1〜8は、Mo、Cr、W、Feま
たはSiの炭化物を有するNi基の硬質粒子を鉄基の基
地組織に分散することにより、近年のバルブシート材な
どの様に、厳しい使用環境に対応でき、耐摩耗性特に高
温における耐摩耗性をより一層向上させた耐摩耗性鉄基
焼結合金およびその製造方法を提供することを目的とす
る。
Therefore, in order to efficiently bring out the effect of the addition of alloying elements, it is conceivable to employ powders in which alloying elements are alloyed with iron in advance. Since the compressibility of the powder is reduced due to the solution hardening, it is difficult to increase the density of the green compact, which is disadvantageous for improving the strength and durability. The present invention has been made to solve the above-described problems in the conventional iron-based sintered alloy. Claims 1 to 8 disclose Ni-based hard particles having carbides of Mo, Cr, W, Fe, or Si in an iron-based matrix, so as to be used in a severe environment such as a valve seat material in recent years. It is an object of the present invention to provide a wear-resistant iron-based sintered alloy further improved in wear resistance, particularly at high temperatures, and a method for producing the same.
【0008】更に請求項4〜8は、鉄基合金粉末に対し
てNi基硬質合金粉末と黒鉛粉末等とを混合した混合粉
末を用いることにより、基地を構成する鉄基合金粉末の
圧縮成形性を確保し、更に焼結によりNi基硬質合金粉
末のNiを基地に拡散させることにより、基地の耐酸化
性を確保し、耐摩耗性特に高温における耐摩耗性を一層
向上させた耐摩耗性鉄基焼結合金の製造方法を提供する
ことを目的とする。
[0008] Further, according to claims 4 to 8, the compression moldability of the iron-based alloy powder constituting the matrix is obtained by using a mixed powder obtained by mixing the Ni-based hard alloy powder and the graphite powder with the iron-based alloy powder. Abrasion-resistant iron that ensures the oxidation resistance of the matrix and further improves the wear resistance, especially at high temperatures, by diffusing Ni of the Ni-based hard alloy powder to the matrix by sintering. An object of the present invention is to provide a method for producing a base sintered alloy.
【0009】更にまた、請求項3、8は、上記した課題
に加えて、上記した焼結合金を構成する焼結体の気孔に
溶浸剤を溶浸することにより、近年のバルブシート材な
どの様に、厳しい使用環境に対応でき、耐摩耗性、特に
高温における耐摩耗性をより一層向上させた耐摩耗性鉄
基焼結合金、その製造方法を提供することを目的とす
る。
Further, in addition to the above-mentioned problems, in addition to the above-mentioned problems, the present invention relates to a recent valve seat material by infiltrating a pore of a sintered body constituting the above-mentioned sintered alloy with an infiltrant. Thus, an object of the present invention is to provide a wear-resistant iron-based sintered alloy which can cope with a severe use environment and further has improved wear resistance, particularly wear resistance at high temperatures, and a method for producing the same.
【0010】[0010]
【課題を解決するための手段】本発明者は、耐摩耗性、
耐腐食性、耐酸化性を向上させるために、バルブシート
用鉄系焼結合金の基地の化学成分と合金化形態、硬質粒
子の種類と添加量、基地組織と焼結条件等々について、
鋭意研究を重ねた。その結果、高温における優れた耐酸
化性と耐腐食性を発揮する基地の特定組成範囲および合
金化形態を見出すと共に、特定組成範囲の炭化物を有す
る硬質粒子をこの基地中に分散させることにより、極め
て良好な耐摩耗性、耐腐食性、耐酸化性を保持しうるこ
とを知見し、且つ従来材に比べて経済性に優れているこ
とを見出して本発明を完成した。
SUMMARY OF THE INVENTION The present inventor has developed a wear resistance,
In order to improve the corrosion resistance and oxidation resistance, the chemical composition and alloying form of the base of the iron-based sintered alloy for valve seats, the type and amount of hard particles, the base structure and the sintering conditions, etc.
We continued our research. As a result, a specific composition range and alloying morphology of a matrix exhibiting excellent oxidation resistance and corrosion resistance at high temperatures are found, and hard particles having carbides in a specific composition range are dispersed in this matrix, thereby extremely The present inventors have found that good abrasion resistance, corrosion resistance, and oxidation resistance can be maintained, and have found that they are more economical than conventional materials, thereby completing the present invention.
【0011】即ち、本発明者は、Niを積極的に含まな
い鉄基合金粉末に対して、Ni基硬質合金粉末と黒鉛粉
末とを混合した混合粉末で圧粉体を形成し、その圧粉体
を所定温度域において焼結することにより、基地を形成
する鉄基合金粉末の圧縮性を確保すること、焼結に伴い
Ni基硬質合金粉末のNiを基地に拡散させることによ
り基地の耐酸化性、特に高温における酸化性を確保する
こと、更に焼結に伴い黒鉛粉末のCを拡散させて基地あ
るいはNi基硬質合金粉末の内部に炭化物を生成し、こ
れにより鉄基焼結合金の耐摩耗性、耐酸化性、耐熱性を
一層確保することを意図している。 ○請求項1の耐摩耗性に優れた鉄基焼結合金は、重量比
で全体組成が、Co;1.4〜15%、Mo;1.5〜
16%、Cr;0.4〜12%、W;0.2〜6.0
%、C;0.4〜3.2%、Ni;0.2〜9.0%を
含有し、残部が不可避不純物とFeからなり、Co;2
〜15%、Mo;2〜10%、C;0.2〜2%、N
i;10%以下を含有し残部が不可避不純物とFeから
なる基地組織に、Mo;5〜20%、Cr;20〜40
%、W;10〜20%、C;0.5〜5.0%、Fe;
5〜30%を含有し、残部が不可避不純物とNiからな
る硬質粒子を2〜30%分散した焼結体からなることを
特徴とするものである。 ○請求項2の耐摩耗性に優れた鉄基焼結合金は、重量比
で全体組成が、Co;1.4〜15%、Mo;1.5〜
16%、Cr;0.4〜12%、W;0.2〜6.0
%、C;0.01〜4.0%、Ni;0.2〜9.0
%、さらにSi;0.6%以下を含有し、残部が不可避
不純物とFeからなり、Co;2〜15%、Mo;2〜
10%、C;0.2〜2%、Ni;10%以下を含有し
残部が不可避不純物とFeからなる基地組織に、Mo;
5〜20%、Cr;20〜40%、W;10〜20%、
C;0.5〜4.0%、Fe;5〜30%、さらにS
i;2%以下を含有し、残部が不可避不純物とNiから
なる硬質粒子を2〜30%分散した焼結体からなること
を特徴とするものである。 ○請求項3の耐摩耗性に優れた鉄基焼結合金は、請求項
1または請求項2記載の焼結体は気孔をもち、気孔内
に、Pb、Cu、Pb−Cu系合金の少なくとも1種を
主要成分とした溶浸剤を、焼結体を重量比で100%と
したとき100%に対して1〜25%溶浸したことを特
徴とするものである。 ○請求項4の耐摩耗性に優れた鉄基焼結合金の製造方法
は、重量比で、Co;2〜15%、Mo;2〜10%を
含有し、残部が不可避不純物とFeからなる鉄基合金粉
末に対して、Mo;5〜20%、Cr;20〜40%、
W;10〜20%、Fe;10〜30%と残部が不可避
不純物とNiからなるNi基硬質合金粉末と、黒鉛粉末
0.2〜2%と成形用潤滑剤とを混合、成形し、132
3KからNi基硬質合金粉末の融点未満の温度で焼結す
ることにより、焼結体からなる鉄基焼結合金を製造する
ことを特徴とするものである。 ○請求項5の鉄基焼結合金の製造方法は、請求項4にお
いて、鉄基粉末合金のMo含有量が3%を越え10%以
下であることを特徴とするものである。 ○請求項6の耐摩耗性に優れた鉄基焼結合金の製造方法
は、重量比で、Co;2〜15%、Mo;2〜10%を
含有し、残部が不可避不純物とFeからなる鉄基合金粉
末に対して、Mo;5〜20%、Cr;20〜40%、
W;10〜20%、Fe;10〜30%と、C;0.5
〜4%、Si;2%以下を含有し残部が不可避不純物と
NiからなるNi基硬質合金粉末と、黒鉛粉末0.2〜
2%と成形用潤滑剤とを混合、成形し、1323Kから
Ni基硬質合金粉末の融点未満の温度で焼結することに
より、焼結体からなる鉄基焼結合金を製造することを特
徴とするものである。 ○請求項7の耐摩耗性に優れた鉄基合金粉末の製造方法
は、請求項6において、鉄基合金粉末のMo含有量が3
%を越え10%以下であることを特徴とするものであ
る。 ○請求項8の耐摩耗性に優れた鉄基焼結合金の製造方法
は、請求項4〜請求項7において、焼結体は気孔をも
ち、気孔内に、Pb、Cu、Pb−Cu系合金の少なく
とも1種を主要成分とした溶浸剤を、焼結体を重量比で
100%としたとき100%に対して1〜25%溶浸し
たことを特徴とするものである。
That is, the present inventor formed a green compact with a mixed powder obtained by mixing a Ni-based hard alloy powder and a graphite powder with respect to an iron-based alloy powder not actively containing Ni. By sintering the body in a predetermined temperature range, it is possible to secure the compressibility of the iron-based alloy powder forming the matrix, and to diffuse the Ni of the Ni-based hard alloy powder into the matrix during sintering to thereby prevent oxidation of the matrix. Properties, especially at high temperatures, and diffuses C in the graphite powder during sintering to form carbides in the matrix or inside the Ni-based hard alloy powder, thereby reducing the wear resistance of the iron-based sintered alloy. It is intended to further ensure the heat resistance, oxidation resistance and heat resistance. The iron-based sintered alloy having excellent wear resistance according to claim 1 has a total composition of 1.4 to 15% by weight of Co and 1.5 to 1.5% by weight of Co.
16%, Cr: 0.4 to 12%, W: 0.2 to 6.0
%, C; 0.4 to 3.2%, Ni; 0.2 to 9.0%, the balance being unavoidable impurities and Fe, Co;
-15%, Mo: 2-10%, C: 0.2-2%, N
i: In a base structure containing 10% or less and the balance consisting of unavoidable impurities and Fe, Mo: 5 to 20%, Cr: 20 to 40
%, W; 10 to 20%, C: 0.5 to 5.0%, Fe;
The sintered body contains 5 to 30% and hard particles composed of inevitable impurities and Ni are dispersed in 2 to 30% in the balance. The iron-based sintered alloy having excellent wear resistance according to claim 2 has a total composition of 1.4 to 15% by weight of Co and 1.5 to 1.5% by weight of Co.
16%, Cr: 0.4 to 12%, W: 0.2 to 6.0
%, C: 0.01 to 4.0%, Ni; 0.2 to 9.0
%, Further Si: 0.6% or less, the balance consists of unavoidable impurities and Fe, Co; 2 to 15%, Mo;
10%, C: 0.2 to 2%, Ni; 10% or less, and the balance is Mo;
5-20%, Cr; 20-40%, W; 10-20%,
C; 0.5 to 4.0%, Fe; 5 to 30%, and further S
i: a sintered body containing 2% or less and hard particles composed of unavoidable impurities and Ni dispersed in 2 to 30% in the balance. The iron-based sintered alloy having excellent wear resistance according to claim 3 is characterized in that the sintered body according to claim 1 or 2 has pores, and at least one of Pb, Cu, and a Pb-Cu alloy is contained in the pores. The infiltrant containing one kind as a main component is infiltrated by 1 to 25% with respect to 100% when the weight of the sintered body is 100%. The method for producing an iron-based sintered alloy having excellent wear resistance according to claim 4 includes, by weight, Co: 2 to 15% and Mo: 2 to 10%, with the balance being unavoidable impurities and Fe. Mo; 5 to 20%, Cr; 20 to 40%, based on the iron-based alloy powder,
W: 10 to 20%, Fe: 10 to 30%, the balance being Ni-based hard alloy powder composed of inevitable impurities and Ni; graphite powder 0.2 to 2%;
The present invention is characterized in that an iron-based sintered alloy made of a sintered body is manufactured by sintering at a temperature from 3K to a temperature lower than the melting point of the Ni-based hard alloy powder. The method for producing an iron-based sintered alloy according to claim 5 is characterized in that, in claim 4, the Mo content of the iron-based powder alloy is more than 3% and 10% or less. The method for producing an iron-based sintered alloy having excellent wear resistance according to claim 6 includes, by weight, Co: 2 to 15% and Mo: 2 to 10%, with the balance being unavoidable impurities and Fe. Mo; 5 to 20%, Cr; 20 to 40%, based on the iron-based alloy powder,
W: 10 to 20%, Fe: 10 to 30%, and C: 0.5
44%, Si; Ni-based hard alloy powder containing 2% or less, the balance being unavoidable impurities and Ni, and graphite powder 0.2-
2% and a molding lubricant are mixed, molded, and sintered at a temperature lower than the melting point of the Ni-based hard alloy powder from 1323 K to produce an iron-based sintered alloy made of a sintered body. Is what you do. The method for producing an iron-based alloy powder having excellent wear resistance according to claim 7 is the method according to claim 6, wherein the Mo content of the iron-based alloy powder is 3%.
% And not more than 10%. The method for producing an iron-based sintered alloy having excellent wear resistance according to claim 8 is the method according to claims 4 to 7, wherein the sintered body has pores, and Pb, Cu, Pb-Cu-based material is contained in the pores. An infiltrant containing at least one of the alloys as a main component is infiltrated by 1 to 25% with respect to 100% when the sintered body is 100% by weight.
【0012】[0012]
【作用】請求項1〜3の鉄基焼結合金において、基地組
織は、Co;2〜15%、Mo;2〜10%、Ni;1
0%以下を固溶した合金元素で構成したので、合金元素
の素地への固溶均質度が高く、従って各種の要素粉末を
混合する従来法に比べて、少ない合金量で優れた耐腐食
性、耐酸化性および耐摩耗性を得ることができる。
In the iron-based sintered alloy according to any one of claims 1 to 3, the base structure is Co: 2 to 15%, Mo: 2 to 10%, Ni: 1
Since less than 0% is composed of solid solution alloy element, the homogeneity of solid solution of the alloy element in the base material is high. Therefore, compared with the conventional method of mixing various element powders, excellent corrosion resistance with less alloy amount. , Oxidation resistance and abrasion resistance.
【0013】請求項1〜3の鉄基焼結合金の基地にはN
iが含まれており、耐酸化性が向上し、更にこの基地に
はMoの炭化物が生成している。請求項4〜8の製造方
法における鉄基合金粉末(Fe−2〜15%Co−2〜
10%Moの組成をもつ合金粉末)は、請求項1〜3の
鉄基焼結合金における基地を構成するものである。請求
項4〜8の製造方法におけるNi基硬質合金粉末は、請
求項1〜3の硬質粒子を構成するものである。この硬質
粒子はNi基硬質合金であってそれ自体硬いものであ
る。さらにこの硬質粒子はC(請求項6の様にNi基硬
質合金粉末にその粉末状態でCが含まれている場合には
そのC、あるいは、請求項4〜8で添加される黒鉛粉末
のC)を含むことによって、Mo、Cr、W、Fe、S
iと結合し、炭化物を形成することにより、硬質粒子自
体の耐摩耗性を一層向上させる。
The base of the iron-based sintered alloy according to claims 1 to 3 is N
i, the oxidation resistance is improved, and Mo carbides are generated in this base. An iron-based alloy powder (Fe-2 to 15% Co-2 or more) in the production method according to claims 4 to 8.
The alloy powder having a composition of 10% Mo) constitutes a matrix in the iron-based sintered alloy according to claims 1 to 3. The Ni-based hard alloy powder in the production method of claims 4 to 8 constitutes the hard particles of claims 1 to 3. The hard particles are a Ni-based hard alloy and are themselves hard. Further, the hard particles are C (C if the Ni-based hard alloy powder contains C in the powder state as in claim 6) or C of the graphite powder added in claims 4 to 8. ), Mo, Cr, W, Fe, S
By forming carbides by combining with i, the wear resistance of the hard particles themselves is further improved.
【0014】請求項4〜8の製造方法において鉄基合金
粉末は前述した様に鉄基焼結合金の基地を構成するもの
であり、粉末状態ではNiを積極的には含まないので、
圧粉体の成形の際において、基地を構成する鉄基合金粉
末自体の圧縮性は確保され、従って圧粉体の高密度化に
有利である。更に、硬質粒子を構成するNi基合金粉末
中のNiは、焼結の際に基地中に拡散して、基地の耐酸
化性、特に高温における耐酸化性や耐熱性を向上させ
る。
In the manufacturing method according to claims 4 to 8, the iron-based alloy powder constitutes the base of the iron-based sintered alloy as described above, and does not actively contain Ni in the powder state.
In molding the green compact, the compressibility of the iron-based alloy powder itself constituting the matrix is ensured, and therefore, it is advantageous for increasing the density of the green compact. Further, Ni in the Ni-based alloy powder constituting the hard particles diffuses into the matrix at the time of sintering, and improves the oxidation resistance of the matrix, particularly the oxidation resistance and heat resistance at high temperatures.
【0015】また請求項4〜8の製造方法において、焼
結の際には、黒鉛粉末のCはNi基硬質合金粉末中のM
o、Cr、W、Fe等と結合して、または、鉄基合金粉
末中のMo等と結合して、炭化物を形成することによ
り、基地及びNi基硬質合金粉末の耐摩耗性を向上させ
る。 (組織)本発明の焼結合金の基地の金属組織は一般的に
はパーライト、オーステナイト、ベイナイトが混在する
組織であると判定される。かかる基地組織には生成した
炭化物が分散している。更に、炭化物を生成したNi基
硬質合金粉末で構成された硬質粒子が上記基地組織に分
散している。 (鉄基合金粉末)請求項4〜8の鉄基合金粉末は前述の
様に本発明の鉄基焼結合金の基地を構成するものであ
り、重量比でCo;2〜15%、Mo;2〜10%を含
有し、残部が不可避不純物とFeからなる。 Co;2〜15% Coは素地に固溶してこれを強化するとともに、耐熱性
および耐腐食性を向上させる効果があるが、鉄基合金粉
末においてCo含有量が2%未満ではその効果が不足
し、一方15%を越えて含有させると、効果のさらなる
向上は見られるものの経済性に欠けるため、この点を考
慮してその含有量を2〜15%と規定した。 Mo;2〜10% Moは、素地に固溶してこれを強化するとともに、高温
域における強度の改善に効果を示し、炭素を含む焼結体
においては一部が炭化物を生成し耐摩耗性の改善に効果
を示す。これらの効果は、鉄基合金粉末において含有量
が2%未満では不十分であり、さらに好ましくは3%を
越えることであり、10%を越えても効果の向上は認め
られるものの、鉄基合金粉末の圧縮性低下を招くため、
その含有量を2〜10%に規定した。上記理由から好ま
しくは鉄基合金粉末においてMoは3%を越え10%以
下が適当である。 (Ni基硬質合金粉末)Ni基硬質合金粉末は鉄基焼結
合金の耐摩耗性の向上に寄与する。このNi基硬質合金
粉末は本発明者等が開発した硬質粒子粉末であり、請求
項1〜3における硬質粒子を構成する。Ni基硬質合金
粉末はMo;5〜20%、Cr;20〜40%、W;1
0〜20%、Fe;10〜30%を含む。Mo、Cr、
W、Si、FeはCと結合し炭化物を形成することによ
り、鉄基焼結合金の耐摩耗性の向上に寄与する。
In the manufacturing method according to claims 4 to 8, C in the graphite powder is replaced by M in the Ni-based hard alloy powder during sintering.
By combining with o, Cr, W, Fe, etc., or with Mo, etc. in the iron-based alloy powder to form a carbide, the wear resistance of the matrix and the Ni-based hard alloy powder is improved. (Structure) The metal structure of the matrix of the sintered alloy of the present invention is generally determined to be a structure in which pearlite, austenite, and bainite are mixed. The generated carbides are dispersed in the matrix. Further, hard particles composed of a Ni-based hard alloy powder that has generated carbides are dispersed in the matrix. (Iron-based alloy powder) The iron-based alloy powder according to claims 4 to 8 constitutes the matrix of the iron-based sintered alloy of the present invention as described above, and has a weight ratio of Co: 2 to 15%, Mo; It contains 2 to 10%, with the balance being unavoidable impurities and Fe. Co; 2 to 15% Co forms a solid solution in the matrix and strengthens it, and also has an effect of improving heat resistance and corrosion resistance. However, when the Co content in the iron-based alloy powder is less than 2%, the effect is reduced. On the other hand, if the content exceeds 15%, the effect is further improved but the economy is low. Therefore, the content is defined as 2 to 15% in consideration of this point. Mo: 2 to 10% Mo forms a solid solution in the base material and strengthens it, and also has an effect of improving the strength in a high temperature region. The effect is improved. These effects are insufficient when the content of the iron-based alloy powder is less than 2%, and more preferably the content is more than 3%. To reduce the compressibility of the powder,
Its content was defined as 2 to 10%. For the above reasons, Mo is preferably more than 3% and 10% or less in the iron-based alloy powder. (Ni-based hard alloy powder) The Ni-based hard alloy powder contributes to improving the wear resistance of the iron-based sintered alloy. The Ni-based hard alloy powder is a hard particle powder developed by the present inventors and constitutes the hard particles according to claims 1 to 3. Ni-based hard alloy powder: Mo; 5 to 20%, Cr: 20 to 40%, W: 1
0-20%, Fe; 10-30%. Mo, Cr,
W, Si, and Fe combine with C to form carbides, thereby contributing to an improvement in wear resistance of the iron-based sintered alloy.
【0016】Ni基硬質合金粉末はさらに必要に応じて
請求項6の様にC;0.5〜4.0%、Si;2%以下
を含有することが好ましい。Ni基硬質合金粉末はFe
を10〜30%含み特に12〜22%なかでも15〜2
0%にできる。Ni基硬質合金粉末つまり硬質粒子中の
Feは、鉄基焼結合金の相手攻撃性を規制することを主
として意図している。その理由はFeの炭化物は他の炭
化物等に比較して硬度が低いためである。なお、Ni基
硬質合金粉末が噴霧法で形成された噴霧粉末である場合
には、Siを含めば噴霧性は確保される。Ni基硬質合
金粉末のNiおよびFeの一部は、焼結により基地中に
拡散し、基地における耐酸化性の向上および硬質粒子の
基地への保持力向上に作用する。
It is preferable that the Ni-based hard alloy powder further contains C: 0.5 to 4.0% and Si: 2% or less, if necessary. Ni-based hard alloy powder is Fe
10 to 30%, especially 12 to 22%, especially 15 to 2
0%. The Fe in the Ni-based hard alloy powder, that is, the hard particles, is mainly intended to regulate the counter-attack of the iron-based sintered alloy. The reason is that the hardness of Fe carbide is lower than that of other carbides. In the case where the Ni-based hard alloy powder is a spray powder formed by a spray method, sprayability is ensured if Si is included. A part of Ni and Fe of the Ni-based hard alloy powder diffuses into the matrix by sintering, and acts to improve the oxidation resistance of the matrix and the holding power of the hard particles to the matrix.
【0017】Ni基硬質合金粉末は、圧粉体を構成する
混合粉末(潤滑剤をのぞく)、つまり焼結体を重量比で
100%としたとき、100%のうちの2〜30%が好
ましい。従って請求項1においては硬質粒子は焼結体全
体を100%としたとき2〜30%に規定されている。
ここでNi基硬質合金粉末の添加量が2%未満では、耐
摩耗性の向上が不十分であり、30%を越えて添加して
も、添加の割に向上が少なく、また成形性の低下を招く
ため、Ni基硬質合金粉末の添加量を2〜30%が妥当
である。さらに上記理由あるいは鉄基焼結合金の用途や
種類に基づき、Ni基硬質合金粉末の量は例えば上限値
が27%、23%、15%にでき、下限値が3%、5
%、8%にできる。
The Ni-based hard alloy powder is preferably 2 to 30% of 100% when the weight ratio of the mixed powder (excluding the lubricant) constituting the green compact, that is, the sintered body is 100%. . Therefore, in claim 1, the hard particles are defined as 2 to 30% when the whole sintered body is 100%.
Here, if the addition amount of the Ni-based hard alloy powder is less than 2%, the improvement of the wear resistance is insufficient, and even if it exceeds 30%, the improvement is small for the addition, and the moldability decreases. Therefore, the addition amount of the Ni-based hard alloy powder is suitably 2 to 30%. Further, based on the above-mentioned reasons or the use and type of the iron-based sintered alloy, the amount of the Ni-based hard alloy powder can be, for example, an upper limit of 27%, 23%, or 15%, and a lower limit of 3% or 5%.
%, 8%.
【0018】以上において鉄基合金粉末およびNi基硬
質合金粉末組成の限定理由を述べたが、鉄基焼結合金中
の基地組織や硬質粒子の組成限定理由も基本的にはこれ
に対応するものである。 (C)Cは基地に固溶し基地を強化するとともに、一部
はNi基硬質合金粉末(基地に分散した硬質粒子に相
当)に拡散し、Ni基硬質合金粉末中のMo、Cr、W
等と結合して炭化物を生成し、Ni基硬質合金粉末つま
り硬質粒子の硬度を高め、耐摩耗性の向上に効果を示
す。Cは黒鉛粉末から供給できる。黒鉛粉末は、圧粉体
を構成する混合粉末全体(潤滑剤をのぞく)、つまり焼
結体を重量比で100%としたとき、100%のうちの
0.2〜2%が好ましい。また請求項6の様にNi基硬
質合金粉末が予めCを含有していても良い。請求項4に
おいて黒鉛粉末の添加量が0.2%未満では前記効果が
あまり期待できず、また2.0%を越えて添加すると焼
結合金を脆化させるおそれがあるので、その添加量は
0.2〜2.0%が好ましい。例えば0.6〜1.3
%、0.7〜1.0%にできる。 (焼結温度)本発明の焼結合金の焼結温度は1323K
からNi基硬質合金粉末の融点未満の温度が好ましい。
焼結温度が1323K未満では、焼結進行が不十分であ
り耐摩耗性が不足するからであり、焼結温度がNi基硬
質合金粉末の融点未満の温度を越えると結晶粒の粗大化
のため好ましくないからである。 (溶浸剤)請求項3、8では焼結合金を構成する焼結体
はスケルトン状であり気孔をもち、気孔に溶浸剤が溶浸
される。溶浸は、より厳しい条件下で使用される耐摩耗
性鉄基焼結合金(例えば内燃機関のバルブシート)に適
する。溶浸された溶浸剤は、相手材(例えばバルブ)と
本発明の鉄基焼結合金との接触部に介在し、潤滑剤とし
て作用する。その結果、相手材(例えばバルブ)と本発
明の鉄基焼結合金(例えばバルブシート)との間におけ
る相互の耐摩耗性や耐焼付性を向上させる。更に、溶浸
剤は本発明の鉄基焼結合金の熱伝導性を向上させること
により、鉄基焼結合金の当り面(例えばバルブシート当
り面)の温度を効率的に低下させ、耐摩耗性、耐焼付性
を一層向上させる。
Although the reasons for limiting the composition of the iron-based alloy powder and the Ni-based hard alloy powder have been described above, the reasons for limiting the base structure and the composition of the hard particles in the iron-based sintered alloy basically correspond to the reasons. It is. (C) C forms a solid solution in the matrix, strengthens the matrix, and partially diffuses into the Ni-based hard alloy powder (corresponding to the hard particles dispersed in the matrix) to form Mo, Cr, W in the Ni-based hard alloy powder.
And the like to form carbides, increase the hardness of the Ni-based hard alloy powder, that is, the hard particles, and exhibit an effect of improving wear resistance. C can be supplied from graphite powder. The graphite powder is preferably 0.2 to 2% of 100% when the weight ratio of the entire mixed powder (excluding the lubricant) constituting the green compact, that is, the sintered body is 100%. Further, the Ni-based hard alloy powder may contain C in advance. In claim 4, if the amount of graphite powder is less than 0.2%, the above effect cannot be expected much. If the amount exceeds 2.0%, the sintered alloy may be embrittled. 0.2-2.0% is preferable. For example, 0.6 to 1.3
%, 0.7 to 1.0%. (Sintering temperature) The sintering temperature of the sintered alloy of the present invention is 1323K.
Therefore, the temperature is preferably lower than the melting point of the Ni-based hard alloy powder.
If the sintering temperature is lower than 1323K, the sintering progress is insufficient and the wear resistance is insufficient. If the sintering temperature exceeds the temperature lower than the melting point of the Ni-based hard alloy powder, the crystal grains become coarse. This is because it is not preferable. (Infiltrant) According to claims 3 and 8, the sintered body constituting the sintered alloy has a skeleton shape and has pores, and the infiltrant is infiltrated into the pores. Infiltration is suitable for wear-resistant iron-based sintered alloys (eg, valve seats for internal combustion engines) used under more severe conditions. The infiltrant infiltrated intervenes at the contact portion between the mating material (for example, a valve) and the iron-based sintered alloy of the present invention, and acts as a lubricant. As a result, the mutual wear resistance and seizure resistance between the mating material (for example, a valve) and the iron-based sintered alloy (for example, a valve seat) of the present invention are improved. Further, the infiltrant improves the thermal conductivity of the iron-based sintered alloy of the present invention, thereby effectively lowering the temperature of the contact surface of the iron-based sintered alloy (for example, the contact surface of the valve seat), thereby reducing the wear resistance. And further improve the seizure resistance.
【0019】請求項3、8では溶浸剤は、焼結体を重量
比で100%としたとき100%に対して1〜25%と
されている。従って溶浸剤の溶浸量が25%のときに
は、溶浸剤/(焼結体+溶浸剤)=25/(100+2
5)の意味である。ここで、溶浸剤が1%未満では、溶
浸の効果があまり発揮できず、25%を超えて溶浸する
と、焼結合金を構成するスケルトンの脆化、弱化などよ
り逆効果を起こす可能性があり、この意味で1%〜25
%が適当であり特に3〜23%なかでも10〜22%が
適当である。
According to the third and eighth aspects, the infiltrant is used in an amount of 1 to 25% with respect to 100% by weight of the sintered body. Therefore, when the infiltration amount of the infiltrant is 25%, the infiltrant / (sintered body + infiltrant) = 25 / (100 + 2)
It means 5). Here, if the infiltrant is less than 1%, the effect of infiltration cannot be sufficiently exerted. If the infiltration exceeds 25%, the opposite effect may be caused due to embrittlement or weakening of the skeleton constituting the sintered alloy. In this sense, 1% to 25
% Is appropriate, and particularly, 3 to 23%, and particularly preferably 10 to 22%.
【0020】溶浸剤としては、鉛、鉛ー銅合金、銅ない
し、これらを主要成分とする金属系が適している。鉛ー
銅合金としては、Cu−30重量%Pbを採用できる。
As the infiltrant, lead, a lead-copper alloy, copper or a metal containing these as a main component is suitable. As the lead-copper alloy, Cu-30% by weight Pb can be adopted.
【0021】[0021]
【実施例】本発明の好適な実施例を比較材と対比して説
明し、本発明の特徴を明らかにする。 (実施例1〜7)これらの例では、重量比でMo;4.
9%、Co;4.6%、残部が実質的にFeである鉄基
噴霧合金粉末Aを用いる。重量比でMo;1.2%、C
o;4.7%、残部が実質的にFeである鉄基噴霧合金
粉末Dを用いる。重量比でMo;2.2%、Co;4.
6%、残部が実質的にFeである鉄基噴霧合金粉末Eを
用いる。重量比でMo;3.1%、Co;4.5%、残
部が実質的にFeである鉄基噴霧合金粉末Fを用いる。
上記した鉄基噴霧合金粉末A、D、E、Fはいずれも粒
径177μm以下である。
DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in comparison with comparative materials to clarify the features of the present invention. (Examples 1 to 7) In these examples, Mo;
9%, Co; 4.6%, and the balance is substantially iron. Mo by weight; 1.2%, C
o: An iron-based spray alloy powder D having 4.7% and the balance substantially Fe is used. Mo: 2.2% by weight; Co;
An iron-based spray alloy powder E having 6% and the balance substantially Fe is used. 3.1% by weight of Mo, 4.5% by weight of Co, the balance being substantially Fe is used.
Each of the iron-based spray alloy powders A, D, E, and F described above has a particle size of 177 μm or less.
【0022】更に、重量比でCr;35.2%、W;1
2.5%、Mo;8.7%、Fe;18.7%、C;
2.6%、Si;0.6%残部が実質的にNiであるN
i基噴霧合金粉末B(粒径149μm以下)を用いる。
更に重量比でCr;26.7%、W;16.2%、M
o;13.3%、Fe;17.0%、Si;0.6%、
C;2.7%、残部が実質的にNiであるNi噴霧合金
粉末C(粒径149μm以下)を用いる。なお上記した
各合金粉末の組成は、各合金粉末自体を重量比で100
%としたときの割合を意味する。
Further, by weight ratio, Cr: 35.2%, W: 1
2.5%, Mo; 8.7%, Fe; 18.7%, C;
2.6%, Si; 0.6% N with the balance being substantially Ni
i-based spray alloy powder B (particle size: 149 μm or less) is used.
Further, by weight ratio, Cr: 26.7%, W: 16.2%, M
o: 13.3%, Fe: 17.0%, Si: 0.6%,
C: 2.7% Ni-spray alloy powder C (having a particle size of 149 μm or less) whose balance is substantially Ni is used. The composition of each alloy powder described above is such that each alloy powder itself is 100% by weight.
% Means the percentage.
【0023】そして上記した合金粉末A〜Fと硬質粒子
(Ni基硬質合金粉末)と黒鉛粉と潤滑ステアリン酸亜
鉛とを、表1に示す配合組成になるように適宜秤量し、
V型混合機で混合し、混合粉末を得た。なお表1は、混
合粉末(焼結に伴い蒸散する潤滑剤をのぞく、即ち、合
金粉末+硬質粒子+黒鉛粉)を重量比で100%とした
ときの割合を示す。
The alloy powders A to F, the hard particles (Ni-based hard alloy powder), the graphite powder, and the lubricating zinc stearate are appropriately weighed so as to have a composition shown in Table 1.
The mixture was mixed with a V-type mixer to obtain a mixed powder. Table 1 shows the ratio when the weight ratio of the mixed powder (excluding the lubricant which evaporates due to sintering, that is, alloy powder + hard particles + graphite powder) is 100% by weight.
【0024】その後、混合粉末を成形圧力7ton/c
2 にて圧縮し、圧粉体を成形した。得られた圧粉体を
分解アンモニアガス雰囲気中で、1393Kの温度で3
0分間焼結し、これにより各実施例1〜7と比較材1、
2を製造した。各実施例1〜7の試験片では、基地組織
に炭化物が分散し、更に、炭化物が生成したNi基の硬
質粒子(Ni基合金粉末)が基地組織に分散している。
表2は、製造した焼結合金の合金組成を示すものであ
る。表2の割合は、焼結合金を重量比で100%とした
ときの割合である。
Then, the mixed powder was compacted at a pressure of 7 ton / c.
It was compressed at m 2 to form a green compact. The obtained green compact is heated in a decomposed ammonia gas atmosphere at a temperature of 1393K for 3 hours.
Sintering for 0 minutes, whereby each of Examples 1 to 7 and Comparative Material 1,
2 was produced. In the test pieces of Examples 1 to 7, carbides are dispersed in the matrix, and further, Ni-based hard particles (Ni-based alloy powder) in which the carbides are formed are dispersed in the matrix.
Table 2 shows the alloy composition of the manufactured sintered alloy. The ratios in Table 2 are ratios when the sintered alloy is 100% by weight.
【0025】[0025]
【表1】 [Table 1]
【0026】[0026]
【表2】 上記実施例1〜7および比較材1〜2の試験片につい
て、実機を模したバルブ−バルブシート試験機を用い、
各試験片の高温における耐摩耗性の評価を行った。この
試験では、各試験片をリング状のバルブシート形状とし
た。この試験装置はプロパンガスの燃焼によってバルブ
とバルブシートを加熱し、カムの駆動によってバルブを
開閉する機構により、バルブとバルブシートの叩き摩耗
状況を再現するものである。
[Table 2] For the test pieces of Examples 1 to 7 and Comparative Materials 1 and 2, using a valve-valve seat tester simulating an actual machine,
Each test piece was evaluated for wear resistance at high temperatures. In this test, each test piece was formed into a ring-shaped valve seat shape. This test device reproduces the beating wear of the valve and the valve seat by a mechanism that heats the valve and the valve seat by burning propane gas and opens and closes the valve by driving a cam.
【0027】上記試験では,相手材であるバルブの材質
をJIS SUH35とし、バルブの温度を1120
K、バルブシートの温度を670Kに保つよう制御し、
カムの回転数を2200rpmにし、運転時間72Ks
の条件で行い、試験片であるバルブシートの摩耗をバル
ブシートの当り幅増加量として測定した。得られた試験
結果を図1に示した。
In the above test, the material of the valve as the mating member was JIS SUH35, and the temperature of the valve was 1120.
K, control to keep the temperature of the valve seat at 670K,
The rotation speed of the cam is set to 2200 rpm, and the operation time is 72 Ks.
The abrasion of the valve seat as a test piece was measured as an increase in the contact width of the valve seat. FIG. 1 shows the obtained test results.
【0028】図1に示す様に、硬質粒子を添加していな
い比較材1の当り幅増加量が205μmであるのに対し
て、本発明の実施例1〜7の当り幅増加量は89〜12
3μmであり、本発明にかかる焼結合金は耐摩耗性に優
れていることが確認された。また、図2は、基地を構成
する合金粉末(表2)中のMo量を横軸にとり、バルブ
シート当り幅加量を横軸にとった線図である。図2の特
性線から明らかなように、Mo含有量が2%を越えると
摩耗量の減少が見られ3%を越えると、試験片の摩耗特
性が安定し、当り幅増加量が100μmをやや越える程
度で安定する。 (実施例8〜11)この例は焼結体に溶浸剤を溶浸させ
る例である。この例では、重量比でMo:4.9%、C
o:4.6%、残部が実質的にFeの粒径177μm以
下の鉄基噴霧合金粉末Aを用いる。この鉄基噴霧合金粉
末Aは、実施例1〜7で用いた鉄基噴霧合金粉末Aと同
様のものである。更に、重量比でCr:35.2%、
W:12.5%、Mo:8.7%、Fe:18.7%、
C:2.6%、Si:0.6%、残部が実質的にNiの
粒径149μm以下のNi基噴霧合金粉末Bを用いる。
このNi基噴霧合金粉末Bは、実施例1〜7で用いたN
i基噴霧合金粉末Bと同様のものである。
As shown in FIG. 1, the contact width increase of Comparative Example 1 to which no hard particles were added was 205 μm, whereas the contact width increase of Examples 1 to 7 of the present invention was 89 to 90 μm. 12
It was 3 μm, and it was confirmed that the sintered alloy according to the present invention had excellent wear resistance. FIG. 2 is a diagram in which the horizontal axis represents the amount of Mo in the alloy powder (Table 2) constituting the matrix, and the horizontal axis represents the width addition per valve seat. As is clear from the characteristic line in FIG. 2, when the Mo content exceeds 2%, the wear amount decreases, and when the Mo content exceeds 3%, the wear characteristics of the test piece are stabilized, and the contact width increase slightly exceeds 100 μm. It stabilizes when it exceeds. (Examples 8 to 11) This example is an example in which an infiltrant is infiltrated into a sintered body. In this example, Mo: 4.9% by weight, C
o: 4.6%, the balance substantially uses iron-based spray alloy powder A having an Fe particle size of 177 μm or less. This iron-based spray alloy powder A is the same as the iron-based spray alloy powder A used in Examples 1 to 7. Furthermore, Cr: 35.2% by weight,
W: 12.5%, Mo: 8.7%, Fe: 18.7%,
C: 2.6%, Si: 0.6%, and the balance is substantially Ni-based spray alloy powder B having a particle size of 149 μm or less.
This Ni-based spray alloy powder B was obtained by using N
It is the same as i-based spray alloy powder B.
【0029】この例でも上記した粉末を黒鉛粉、潤滑剤
ステアリン酸亜鉛粉とともに、表3に示す配合組成にな
るよう秤量後、V型混合機により混粉を行ない、混合粉
末を得た。次にこの混合粉末を成形圧力7ton/cm
2 にて圧縮し、試験片を作成した。ただし、実施例10
については、成形圧力6.3ton/cm2 にて圧縮
し、試験片を作成した。実施例10の試験片における溶
浸剤の割合を増加させるためである。続いて、窒素ガス
を吹き込む窒素雰囲気にて1404Kに30分間保持
し、焼結を実施した。焼結した後の試験片は、焼結時と
同一雰囲気、同一温度条件にて溶浸処理を行った。溶浸
処理は試験片の上に溶浸剤を置いて行った。溶浸剤は、
表3に示す様に実施例8〜10ではPbを用い、実施例
11ではCuー30重量%Pbを用いた。比較材3は溶
浸処理されていない。
In this example, the above powder was weighed together with the graphite powder and the lubricant zinc stearate so as to have the composition shown in Table 3, and then mixed with a V-type mixer to obtain a mixed powder. Next, this mixed powder was molded at a pressure of 7 ton / cm.
The specimen was compressed by 2 to prepare a test piece. However, Example 10
Was compressed at a molding pressure of 6.3 ton / cm 2 to prepare a test piece. This is because the proportion of the infiltrant in the test piece of Example 10 was increased. Subsequently, sintering was performed by maintaining the temperature at 1404K for 30 minutes in a nitrogen atmosphere into which nitrogen gas was blown. The test piece after sintering was subjected to infiltration treatment under the same atmosphere and the same temperature conditions as during sintering. The infiltration treatment was performed by placing an infiltrant on the test piece. The infiltrant is
As shown in Table 3, in Examples 8 to 10, Pb was used, and in Example 11, Cu-30% by weight Pb was used. Comparative material 3 was not infiltrated.
【0030】得られた試験片について以下に示す条件で
大越式摩耗試験を実施した。試験結果は、比較材3を1
00とした相対表示で表4に示した。大越摩耗試験条件
は以下の様である。即ち、相手材(リング状ロータ)の
材質はJIS SUH35であり、ブロック材は実施例
及び比較材の試験片(固定式)であり、すべり速度は
0.51m/sであり、摩擦距離は100mであり、試
験開始前の温度は相手材が773Kで、ブロック材が6
93Kであり、最終荷重は31.5Nであり、測定項目
はブロック材の摩耗痕幅である。
An Ogoshi type abrasion test was performed on the obtained test piece under the following conditions. The test result shows that Comparative Material 3 was 1
The results are shown in Table 4 with a relative display of 00. The Ogoshi wear test conditions are as follows. That is, the material of the mating material (ring-shaped rotor) is JIS SUH35, the block material is a test piece (fixed type) of the example and the comparative material, the slip speed is 0.51 m / s, and the friction distance is 100 m. The temperature before the start of the test was 773K for the mating material and 6 for the block material.
It was 93K, the final load was 31.5N, and the measurement item was the width of the wear mark of the block material.
【0031】[0031]
【表3】 [Table 3]
【0032】[0032]
【表4】 ここで実施例8〜11と比較材3の比較から明らかな様
に、溶浸することにより摩耗痕幅は、溶浸量に応じて減
少している。従って、溶浸剤による効果の若干の違いは
みられるが、溶浸の効果は大きいことが明らかである。
しかし、実施例9、10を比較すると、溶浸量の多い実
施例10の方が逆に試験片の摩耗痕幅は大きい。これ
は、溶浸量には適性範囲が存在し、溶浸量の増加による
摩耗痕幅減少効果以上に、スケルトンの弱化が始まって
いるためと考えられる。従って溶浸量は1〜25%が妥
当である。 (その他)焼結は上記した場合に限らず、真空、不活性
ガス雰囲気等でもよく、要するに非酸化性雰囲気で行な
うことができる。請求項では鉄基合金粉末のCoは2〜
15%とされているが、鉄基焼結合金の用途や種類に応
じて上限値は13%、10%、8%、6%、5%にでき
下限値は3%にできる。また請求項では鉄基合金粉末の
Moは2〜10%とされているが、鉄基焼結合金の用途
や種類に応じて、上限値は8%、7%、6%にでき下限
値は2.5%、3%にできる。また請求項ではNi基硬
質合金粉末はMo;5〜20%、Cr;20〜40%、
W;10〜20%を含むが、Moは6〜18%なかでも
7〜13%にでき、Crは22〜40%なかでも30〜
40%にでき、Wは11〜19%なかでも12〜18%
にできる。
[Table 4] Here, as is clear from the comparison between Examples 8 to 11 and Comparative Material 3, the width of the wear mark is reduced by infiltration according to the amount of infiltration. Therefore, although the effect of the infiltration agent is slightly different, it is clear that the effect of the infiltration is large.
However, when Examples 9 and 10 are compared, Example 10 having a larger amount of infiltration has a larger wear scar width of the test piece. This is considered to be because the infiltration amount has an appropriate range, and the skeleton has begun to weaken more than the effect of reducing the width of the wear mark by increasing the amount of infiltration. Therefore, an appropriate amount of infiltration is 1 to 25%. (Others) The sintering is not limited to the above-described case, but may be performed in a vacuum, an inert gas atmosphere, or the like. In the claims, Co of the iron-based alloy powder is 2 to 2.
The upper limit can be 13%, 10%, 8%, 6%, and 5%, and the lower limit can be 3%, depending on the use and type of the iron-based sintered alloy. In the claims, the Mo of the iron-based alloy powder is set to 2 to 10%, but the upper limit can be set to 8%, 7%, and 6% depending on the use and the type of the iron-based sintered alloy. 2.5% and 3%. In the claims, the Ni-based hard alloy powder is Mo: 5 to 20%, Cr: 20 to 40%,
W: contains 10 to 20%, but Mo can be made 7 to 13% out of 6 to 18%, and Cr can be made 30 to 30 out of 22 to 40%.
40%, W is 11-19%, 12-18%
Can be.
【0033】請求項6のNi基硬質合金粉末はC;0.
5〜4.0%、Si;2%以下を含有する。このうちC
は上限値が3.5%、3.2%にでき下限値は0.8
%、1.0%にでき、Siは上限値が1.0%、0.5
%にできる。上記した組成の規定は鉄基焼結合金の基地
組織や硬質粒子の組成においても同様に適用可能であ
る。
The Ni-based hard alloy powder according to claim 6 is C;
Contains 5 to 4.0%, Si; 2% or less. Of which C
The upper limit can be 3.5% and 3.2%, and the lower limit is 0.8
%, 1.0%, and the upper limit of Si is 1.0%, 0.5%.
%. The above definition of the composition is similarly applicable to the base structure of the iron-based sintered alloy and the composition of the hard particles.
【0034】[0034]
【発明の効果】本発明の耐摩耗性鉄基焼結合金およびそ
の製造方法の発明は以上説明したように、重量比で、C
o;2〜15%、Mo;2〜10%を含有し、残部が不
可避不純物とFeからなる鉄基合金粉末に対して、M
o;5〜20%、Cr;20〜40%、W;10〜20
%、Fe;10〜30%を含有し、さらに必要に応じて
とC;0.5〜4%、Si;2%以下を含有し残部が不
可避不純物とNiからなるNi基硬質合金粉末と、黒鉛
粉末0.2〜2%と成形用潤滑剤を混合、成形し、13
23KからNi基硬質合金粉末の融点未満の温度で焼結
するものであって、鉄基焼結合金の基地組織に分散した
硬質粒子は、Ni基硬質合金であって、それ自体硬いも
のであるが、さらに、Cを含むことによって、Mo、C
r、W、Si、Feと結合し、炭化物を形成することに
より、耐摩耗性を一層向上させる。
As described above, the invention of the wear-resistant iron-based sintered alloy and the method for producing the same according to the present invention is as follows.
o: 2 to 15%, Mo: 2 to 10%, with the balance being based on the iron-based alloy powder containing unavoidable impurities and Fe.
o: 5 to 20%, Cr: 20 to 40%, W: 10 to 20
%, Fe; 10 to 30%, and if necessary, C: 0.5 to 4%, Si; Ni-based hard alloy powder containing 2% or less, the balance being unavoidable impurities and Ni; Mix and mold 0.2 to 2% of graphite powder and lubricant for molding
The hard particles that are sintered at a temperature lower than the melting point of the Ni-based hard alloy powder from 23K and are dispersed in the base structure of the iron-based sintered alloy are Ni-based hard alloys and are themselves hard. Can further include Mo, C
By combining with r, W, Si, and Fe to form a carbide, wear resistance is further improved.
【0035】請求項4〜8は、鉄基合金粉末に対してN
i基硬質合金粉末と黒鉛粉末等とを混合した混合粉末を
用いるため、鉄基合金粉末は積極的にはNiを含まず、
従って、基地を構成する鉄基合金粉末の過剰硬化を回避
でき、鉄基合金粉末の圧縮成形性を確保できる。更に焼
結によりNi基硬質合金粉末のNiを基地に拡散させる
ことにより、焼結合金の基地の耐酸化性、特に高温にお
ける耐酸化性、耐熱性を確保できる。
Claims 4 to 8 are based on the iron-based alloy powder.
Since the mixed powder obtained by mixing the i-based hard alloy powder and the graphite powder and the like is used, the iron-based alloy powder does not actively contain Ni,
Therefore, excessive hardening of the iron-based alloy powder constituting the matrix can be avoided, and compression-moldability of the iron-based alloy powder can be ensured. Furthermore, by diffusing Ni of the Ni-based hard alloy powder into the matrix by sintering, the oxidation resistance of the matrix of the sintered alloy, particularly the oxidation resistance and heat resistance at a high temperature, can be secured.
【0036】更に請求項3、8では、Pb、Cu、Pb
−Cu系合金の少なくとも1種を主要成分とする溶浸剤
を溶浸しているので、本発明の鉄基焼結合金と相手材と
の接触部に溶浸剤が介在して潤滑剤として機能する効果
を期待でき、耐摩耗性、耐焼付性の向上を期待できる。
更に溶浸剤は鉄基焼結合金の熱伝導性を向上させ、相手
材との接触部の温度の上昇防止に有利である効果を期待
でき、この意味でも耐摩耗性を一層向上させる。
Further, according to the third and eighth aspects, Pb, Cu, Pb
-Since the infiltrant containing at least one of the Cu-based alloys as the main component is infiltrated, the effect that the infiltrant intervenes at the contact portion between the iron-based sintered alloy of the present invention and the counterpart material to function as a lubricant Can be expected, and improvement in wear resistance and seizure resistance can be expected.
Furthermore, the infiltrant can improve the thermal conductivity of the iron-based sintered alloy, and can be expected to have an advantageous effect of preventing an increase in the temperature of the contact portion with the counterpart material. In this sense, the wear resistance is further improved.
【図面の簡単な説明】[Brief description of the drawings]
【図1】摩耗試験における本発明の実施例と比較材のバ
ルブシートの当り幅増加数を示す図である。
FIG. 1 is a view showing the number of contact width increases of a valve seat of an example of the present invention and a comparative material in a wear test.
【図2】摩耗試験におけるバルブシートの当り幅増加数
と基地中のMo量との関係を示す線図である。
FIG. 2 is a diagram showing the relationship between the number of increase in the contact width of a valve seat in a wear test and the amount of Mo in a base.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 伊藤 与志彦 愛知県豊田市トヨタ町1番地 トヨタ自 動車株式会社内 (58)調査した分野(Int.Cl.7,DB名) C22C 33/02 B22F 3/26 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yoshihiko Ito 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (58) Field surveyed (Int.Cl. 7 , DB name) C22C 33/02 B22F 3 / 26

Claims (8)

    (57)【特許請求の範囲】(57) [Claims]
  1. 【請求項1】重量比で全体組成が、Co;1.4〜15
    %、Mo;1.5〜16%、Cr;0.4〜12%、
    W;0.2〜6.0%、C;0.4〜3.2%、Ni;
    0.2〜9.0%を含有し、残部が不可避不純物とFe
    からなり、 Co;2〜15%、Mo;2〜10%、C;0.2〜2
    %、Ni;10%以下を含有し残部が不可避不純物とF
    eからなる基地組織に、 Mo;5〜20%、Cr;20〜40%、W;10〜2
    0%、C;0.5〜5.0%、Fe;5〜30%を含有
    し、残部が不可避不純物とNiからなる硬質粒子を2〜
    30%分散した焼結体からなることを特徴とする耐摩耗
    性に優れた鉄基焼結合金。
    1. The total composition is Co; 1.4 to 15 in weight ratio.
    %, Mo; 1.5 to 16%, Cr; 0.4 to 12%,
    W; 0.2-6.0%, C; 0.4-3.2%, Ni;
    0.2-9.0%, the balance being unavoidable impurities and Fe
    Co; 2 to 15%, Mo: 2 to 10%, C: 0.2 to 2
    %, Ni; 10% or less, the balance being unavoidable impurities and F
    e; Mo: 5-20%, Cr: 20-40%, W: 10-2
    0%, C: 0.5 to 5.0%, Fe: 5 to 30%, the balance being 2 to 2 hard particles composed of unavoidable impurities and Ni.
    An iron-based sintered alloy having excellent wear resistance, comprising a sintered body dispersed in 30%.
  2. 【請求項2】重量比で全体組成が、Co;1.4〜15
    %、Mo;1.5〜16%、Cr;0.4〜12%、
    W;0.2〜6.0%、C;0.01〜4.0%、N
    i;0.2〜9.0%、さらにSi;0.6%以下を含
    有し、残部が不可避不純物とFeからなり、 Co;2〜15%、Mo;2〜10%、C;0.2〜2
    %、Ni;10%以下を含有し残部が不可避不純物とF
    eからなる基地組織に、 Mo;5〜20%、Cr;20〜40%、W;10〜2
    0%、C;0.5〜4.0%、Fe;5〜30%、さら
    にSi;2%以下を含有し、残部が不可避不純物とNi
    からなる硬質粒子を2〜30%分散した焼結体からなる
    ことを特徴とする耐摩耗性に優れた鉄基焼結合金。
    2. The total composition by weight is Co;
    %, Mo; 1.5 to 16%, Cr; 0.4 to 12%,
    W: 0.2 to 6.0%, C: 0.01 to 4.0%, N
    i: 0.2 to 9.0%, further contains Si: 0.6% or less, and the balance consists of unavoidable impurities and Fe. Co: 2 to 15%, Mo: 2 to 10%, C; 2-2
    %, Ni; 10% or less, the balance being unavoidable impurities and F
    e; Mo: 5-20%, Cr: 20-40%, W: 10-2
    0%, C: 0.5 to 4.0%, Fe: 5 to 30%, and Si: 2% or less, with the balance being unavoidable impurities and Ni
    An iron-based sintered alloy having excellent wear resistance, comprising a sintered body in which hard particles of 2 to 30% are dispersed.
  3. 【請求項3】請求項1または請求項2記載の焼結体は気
    孔をもち、該気孔内に、Pb、Cu、Pb−Cu系合金
    の少なくとも1種を主要成分とした溶浸剤を、該焼結体
    を重量比で100%としたとき100%に対して1〜2
    5%溶浸したことを特徴とする耐摩耗性に優れた鉄基焼
    結合金。
    3. The sintered body according to claim 1 or 2, wherein the sintered body has pores, and an infiltrant containing at least one of Pb, Cu, and a Pb-Cu alloy as a main component is contained in the pores. When the weight ratio of the sintered body is 100%, 100%
    Iron-based sintered alloy with excellent wear resistance characterized by infiltration of 5%.
  4. 【請求項4】重量比でCo;2〜15%、Mo;2〜1
    0%を含有し、残部が不可避不純物とFeからなる鉄基
    合金粉末に対して、 Mo;5〜20%、Cr;20〜40%、W;10〜2
    0%、Fe;10〜30%と残部が不可避不純物とNi
    からなるNi基硬質合金粉末と、 黒鉛粉末0.2〜2%と成形用潤滑剤とを混合、成形
    し、 1323Kから該Ni基硬質合金粉末の融点未満の温度
    で焼結することにより、焼結体からなる鉄基焼結合金を
    製造することを特徴とする耐摩耗性に優れた鉄基焼結合
    金の製造方法。
    4. A weight ratio of Co: 2 to 15%, Mo: 2-1.
    Mo: 5 to 20%, Cr: 20 to 40%, W: 10 to 2 with respect to an iron-based alloy powder containing 0% and the balance being unavoidable impurities and Fe.
    0%, Fe; 10 to 30%, the balance being unavoidable impurities and Ni
    By mixing and molding 0.2 to 2% of graphite powder and a molding lubricant, and sintering from 1323 K to a temperature lower than the melting point of the Ni-based hard alloy powder. A method for producing an iron-based sintered alloy having excellent wear resistance, comprising producing an iron-based sintered alloy comprising a sintered body.
  5. 【請求項5】鉄基粉末合金のMo含有量が3%を越え1
    0%以下であることを特徴とする請求項4に記載の耐摩
    耗性に優れた鉄基焼結合金の製造方法。
    5. The Mo content of the iron-based powder alloy exceeds 3%.
    The method for producing an iron-based sintered alloy having excellent wear resistance according to claim 4, wherein the content is 0% or less.
  6. 【請求項6】重量比で、Co;2〜15%、Mo;2〜
    10%を含有し、残部が不可避不純物とFeからなる鉄
    基合金粉末に対して、 Mo;5〜20%、Cr;20〜40%、W;10〜2
    0%、Fe;10〜30%と、C;0.5〜4%、S
    i;2%以下を含有し残部が不可避不純物とNiからな
    るNi基硬質合金粉末と、 黒鉛粉末0.2〜2%と成形用潤滑剤とを混合、成形
    し、 1323KからNi基硬質合金粉末の融点未満の温度で
    焼結することにより、焼結体からなる鉄基焼結合金を製
    造することを特徴とする耐摩耗性に優れた鉄基焼結合金
    の製造方法。
    6. Co: 2 to 15% by weight, Mo: 2 to 2% by weight.
    Mo: 5 to 20%, Cr: 20 to 40%, W: 10 to 2 with respect to an iron-based alloy powder containing 10% and the balance being unavoidable impurities and Fe.
    0%, Fe; 10 to 30%, C: 0.5 to 4%, S
    i; Ni-based hard alloy powder containing 2% or less and the balance being unavoidable impurities and Ni; graphite powder 0.2 to 2% and molding lubricant mixed and molded; 1323K to Ni-based hard alloy powder A method for producing an iron-based sintered alloy having excellent wear resistance, characterized by producing an iron-based sintered alloy comprising a sintered body by sintering at a temperature lower than the melting point of the iron-based sintered alloy.
  7. 【請求項7】鉄基合金粉末のMo含有量が3%を越え1
    0%以下であることを特徴とする請求項6に記載の耐摩
    耗性に優れた鉄基焼結合金の製造方法。
    7. The Mo content of the iron-based alloy powder exceeds 3%.
    The method for producing an iron-based sintered alloy having excellent wear resistance according to claim 6, wherein the content is 0% or less.
  8. 【請求項8】請求項4〜請求項7に記載の焼結体は気孔
    をもち、該気孔内に、Pb、Cu、Pb−Cu系合金の
    少なくとも1種を主要成分とした溶浸剤を、該焼結体を
    重量比で100%としたとき100%に対して1〜25
    %溶浸したことを特徴とする耐摩耗性に優れた鉄基焼結
    合金の製造方法。
    8. The sintered body according to claim 4, wherein the sintered body has pores, and in the pores, an infiltrant containing at least one of Pb, Cu, and a Pb-Cu alloy as a main component is used. When the sintered body is 100% by weight, 1 to 25
    A method for producing an iron-based sintered alloy having excellent wear resistance, characterized by being infiltrated by%.
JP11797094A 1993-09-24 1994-05-31 Wear-resistant iron-based sintered alloy and method for producing the same Expired - Fee Related JP3264092B2 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP23844993 1993-09-24
JP5-238449 1993-09-24
JP11797094A JP3264092B2 (en) 1993-09-24 1994-05-31 Wear-resistant iron-based sintered alloy and method for producing the same

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11797094A JP3264092B2 (en) 1993-09-24 1994-05-31 Wear-resistant iron-based sintered alloy and method for producing the same

Publications (2)

Publication Number Publication Date
JPH07138714A JPH07138714A (en) 1995-05-30
JP3264092B2 true JP3264092B2 (en) 2002-03-11

Family

ID=26455993

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11797094A Expired - Fee Related JP3264092B2 (en) 1993-09-24 1994-05-31 Wear-resistant iron-based sintered alloy and method for producing the same

Country Status (1)

Country Link
JP (1) JP3264092B2 (en)

Also Published As

Publication number Publication date
JPH07138714A (en) 1995-05-30

Similar Documents

Publication Publication Date Title
JP2957180B2 (en) Wear-resistant iron-based sintered alloy and method for producing the same
JP4213060B2 (en) Ferrous sintered alloy material for valve seats
US8733313B2 (en) Iron-based sintered alloy for valve seat, and valve seat for internal combustion engine
JP4299042B2 (en) Iron-based sintered alloy, valve seat ring, raw material powder for producing iron-based sintered alloy, and method for producing iron-based sintered alloy
JP2001050020A (en) Valve device for internal combustion engine
JPH1112697A (en) Valve seat for internal combustion engine
US20020084004A1 (en) Iron-based sintered alloy material for valve seat and valve seat made of iron-based sintered alloy
JP2007023383A (en) Sintered valve seat and production method therefor
JP4693170B2 (en) Wear-resistant sintered alloy and method for producing the same
JP3763782B2 (en) Method for producing wear-resistant iron-based sintered alloy material for valve seat
JPH1121659A (en) Wear resistant iron-base sintered alloy material
JP3434527B2 (en) Sintered alloy for valve seat
JP3186816B2 (en) Sintered alloy for valve seat
JP3225649B2 (en) Wear resistant iron-based sintered alloy
JP3264092B2 (en) Wear-resistant iron-based sintered alloy and method for producing the same
JP3809944B2 (en) Hard particle dispersed sintered alloy and method for producing the same
JP3942136B2 (en) Iron-based sintered alloy
JP3569166B2 (en) Wear-resistant sintered alloy and method for producing the same
JP3784926B2 (en) Ferrous sintered alloy for valve seat
JPH09256120A (en) Powder metallurgy material excellent in wear resistance
JP3226618B2 (en) Iron-based sintered alloy for valve seat
JP3068127B2 (en) Wear-resistant iron-based sintered alloy and method for producing the same
JP2716575B2 (en) Manufacturing method of wear resistant iron-based sintered alloy
JP3068128B2 (en) Wear-resistant iron-based sintered alloy and method for producing the same
JP3573872B2 (en) Method of manufacturing sintered alloy joint valve seat and sintered alloy material for joint valve seat

Legal Events

Date Code Title Description
FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20081228

Year of fee payment: 7

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

Free format text: PAYMENT UNTIL: 20081228

Year of fee payment: 7

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

Free format text: PAYMENT UNTIL: 20091228

Year of fee payment: 8

LAPS Cancellation because of no payment of annual fees