JPS63105947A - Combination of sliding members - Google Patents

Abstract

PURPOSE:To obtain an optimum combination of sliding members reduced in wear, by combining a sliding member having a specific metallic structural body in which a hard phase is phase is dispersed with a sliding member made of ferrous metal in which remelting hardening treatment is applied to a sliding surface layer by means of high density energy irradiation. CONSTITUTION:At least the sliding surface layer of the primary sliding member is formed into a metallic structural body in which a hard phase is dispersed in a matrix phase. On the other hand, the secondary sliding member to be in sliding contact with the above is constituted of a ferrous metal. By using both of the above sliding members, a combination of sliding members which form a couple and mutually slide under high surface pressure is obtained. In the above combination, 4-15mum grains comprise >=80% of the hard layer of the above primary sliding member and the hard phase is dispersed so that average grain spacing and space factor of visual field are regulated to 5-15mum and 10-50%, respectively. On the other hand, remelting hardening treatment is applied to the sliding surface layer of the secondary sliding member by means of high density energy irradiation. An this time, it is desirable that at least one carbide-stabilizing element among Cr, Mo, V, and Nb is forcedly added to the above sliding surface layer. In this way, the combination of sliding members minimal in wear loss and excellent in durability can be obtained.

Description

【発明の詳細な説明】 Ｌｌ上五五ユニ１ 本発明は、大きな血圧の下で相互に摺動する対をなす摺
動部材の組合せに関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a combination of paired sliding members that slide against each other under high blood pressure.

正釆且韮 内燃機関の動弁機構において、カムおよびこれと摺動接
触するロッカアーム（その溶接面部）は、優れた耐摩耗
性を要求される。In the valve mechanism of a straight-button internal combustion engine, the cam and the rocker arm (its welded surface) that make sliding contact with the cam are required to have excellent wear resistance.

それ故、従来鋳鉄製カム軸（例、ＪＩＳ　ＦＣ２５〜３
０材製１合金鋳鉄製）が多用され、鋳造の際に冷し金を
用いてカム表面にチル層を形成するか、あるいは鋳造後
にカム作動面である摺接面部に再溶融硬化処理（炎また
は高周波加熱により溶融後、自己冷却させる）を施して
チル層を形成する等の手法が採用されている。Therefore, conventional cast iron camshafts (e.g., JIS FC25~3
0 material, 1 alloy cast iron) is often used, and either a chilled layer is used to form a chill layer on the cam surface during casting, or a remelting hardening treatment (flame hardening) is applied to the sliding surface, which is the cam operating surface, after casting. Alternatively, methods such as forming a chill layer by melting by high-frequency heating and then self-cooling have been adopted.

また、ロッカアームは、Ｒ造銅、鋳鋼９合金鋳鉄等で作
られ、対カム摺接面に熱処理による表面硬化、浸炭焼入
れ、チル硬化、硬質Ｃｒメッキ等が施されたものとして
提供されていた。In addition, the rocker arm was made of R copper, cast steel, 9 alloy cast iron, etc., and the sliding contact surface with the cam was surface hardened by heat treatment, carburized and quenched, chill hardened, hard Cr plating, etc. were provided.

が　゛しよ〜と　　い　− しかるに、最近では、内燃８Ｎ関の高速化、高出力化に
伴い、カム表面の摺動面圧が増大し、従来に比して高い
耐摩耗性が要求されるところから、鋳造時にカム軸のカ
ム表面部にチル層を形成しても、十分な耐摩耗性を発揮
できなくなっている。However, in recent years, with the increase in speed and output of internal combustion 8N engines, the sliding surface pressure on the cam surface has increased, requiring higher wear resistance than before. Therefore, even if a chill layer is formed on the cam surface of the camshaft during casting, sufficient wear resistance cannot be exhibited.

また、鋳造後の再溶ＷＩＩＵｉＪ、化処理により子処理
を形成した場合、鋳造時に形成するチル層に比して高い
耐摩耗性が得られるものの、十分満足できるとは言い難
い。Further, when a child treatment is formed by remelting WIIUiJ or chemical treatment after casting, higher wear resistance can be obtained compared to the chill layer formed during casting, but it cannot be said to be fully satisfactory.

一方、カムと摺接するロッカアームについて言えば、浸
炭焼入れ材は耐スカツフ性（注：スカッフとは、摩擦面
間の凝着が激しく、それによって表面肌が荒れる現象を
言う）に劣り、チル硬化材は耐久性に劣り、硬質Ｏｒメ
ッキ材は局部当りに伴う剥離あるいは摩耗剥離を生じる
ことがある等。On the other hand, when it comes to the rocker arm that makes sliding contact with the cam, carburized and quenched materials are inferior in scuffing resistance (note: scuffing is a phenomenon in which there is severe adhesion between friction surfaces, resulting in rough surface skin), and chill-hardened materials are inferior in scuffing resistance. has poor durability, and hard Or plating materials may peel off due to local contact or wear and tear.

それぞれに問題を有している。Each has its own problems.

しかも、カムとロッカアームとの閣動接触に伴う摩耗は
、両者の材質の組合せによって左右され、その選択は難
しい問題である。この要求に応えるものとして、鉄基焼
結合金で形成された対カム摺動部材が提案されており、
それ等合金においては、基地相（マトリックス相）中に
分散して硬度を左右する炭化物の大きさ、吊（視野占有
面積率）等。Moreover, the wear caused by the mechanical contact between the cam and the rocker arm depends on the combination of the materials of the two, and selection is a difficult problem. In order to meet this demand, a cam sliding member made of an iron-based sintered alloy has been proposed.
In such alloys, the size of carbides dispersed in the base phase (matrix phase), which affects hardness, and the ratio of the area occupied by the field of view.

諸因子を規定し、カムの摩耗を抑制しつつ、耐摩耗性、
耐スカツフ性等の改善を計っている（例、特公昭５９−
７００３号公報、特開昭６０−６３３５０号公報。By specifying various factors, while suppressing cam wear, wear resistance,
Efforts are being made to improve scuff resistance, etc. (e.g.,
No. 7003, Japanese Patent Application Laid-open No. 60-63350.

特開昭６０−１５５６５０号公報参照）。(See Japanese Patent Application Laid-open No. 155650/1983).

ところが、従来の鉄基焼結合金における炭化物に関する
諸因子の把握の仕方では、組織全体の構造が明らかでな
く、必ずしも所期の目的を達成することはできない。However, with the conventional method of understanding various factors related to carbides in iron-based sintered alloys, the overall structure is not clear, and the intended purpose cannot necessarily be achieved.

ｍ　　るた　の　　およ 本発明は斯かる技術的背須の下に創案されたものであり
、その目的とする処は、摩耗の少ない摺動部材の最適な
組合せを提供する点にある。The present invention was devised based on such technical considerations, and its purpose is to provide an optimal combination of sliding members with less wear.

この目的は、少なくともその摺動表面層が基地相中に硬
質相が分散した金属組織体として形成された第一摺動部
材と、これに摺接する鉄系全屈製第二摺動部材との組合
せであって、第一摺動部材の基地相中に平均粒子間隔５
〜１５μｍ、視野占有面積率１０〜５０％で分散した硬
質相の８０％以上を大きさ４〜１５μｍの粒子が占めて
おり、第二摺動部材は、その摺動表面層に高密度エネル
ギー照射による再溶融硬化処理が施されていることを特
徴とする摺動部材の組合せを提供することにより達成さ
れる。This purpose is to provide at least a first sliding member whose sliding surface layer is formed as a metal structure in which a hard phase is dispersed in a base phase, and a second sliding member made of iron-based fully bendable material that is in sliding contact with the first sliding member. combination, wherein the base phase of the first sliding member has an average particle spacing of 5
Particles with a size of 4 to 15 μm account for more than 80% of the hard phase dispersed with a viewing area ratio of 10 to 50%, and the second sliding member has its sliding surface layer irradiated with high-density energy. This is achieved by providing a combination of sliding members characterized by being subjected to a remelting and hardening treatment.

基地相中に硬質相を分散させることにより、基地相の強
化をも合せて全屈材料の耐摩耗性を向上させる手法は従
来周知であり、分散させる硬質相の大きさ、曾を変化さ
せて当該摺動部材の耐摩耗性の向上を計るとともに、対
接する相手部材の摩耗を可及的に抑えることが可能であ
る。しかるに、実際問題としては、硬質相の大きさ、蚤
を規定するだけでは十分でなく、硬質相の分散状態をも
規定して初めて材料の特性が定まるのである。A method of improving the wear resistance of a fully flexural material by dispersing a hard phase in the base phase, which also strengthens the base phase, is well known. It is possible to improve the wear resistance of the sliding member and to suppress the wear of the opposing member as much as possible. However, as a practical matter, it is not enough to simply specify the size and flea of the hard phase, but the properties of the material can only be determined by specifying the state of dispersion of the hard phase.

本発明者等の試験の結果によれば、硬質相についての有
効規定因子は、大きさく粒子径）、量（視野占有面積率
）１粒子間隔であることが判った。しかも、ここで留意
すべきは、単にそれ等の因子を規定するだけでは本来の
意味で規定したことにはならず、硬質相の存在状態を測
定する方法を明確に定義しなければならない点である。According to the results of the tests conducted by the present inventors, it was found that the effective determining factors for the hard phase are the size (particle diameter) and the amount (visual field area ratio) of one particle interval. Moreover, it should be noted here that simply specifying these factors does not mean that they have been specified in the original sense; the method for measuring the state of existence of the hard phase must be clearly defined. be.

そこで、本発明者等の採用した測定方法は下記の通りで
ある。Therefore, the measurement method adopted by the present inventors is as follows.

■硬質相の大きさく粒子径）　：　ＪＩＳ−Ｇ−０５５
２“鋼のフェライト結晶粒度試験方法”における切断法
を応用したものであり、試料の切断断面を研磨仕上げし
て腐蝕し、腐蝕面を顕微鏡で観察するか、または顕微鏡
写真に撮影して、一定の長さの直交する二本の線分で切
断される炭化物粒子の数と長さの総和から、次式によっ
て平均粒子径を求める。■Hard phase size (particle diameter): JIS-G-055
2. This is an application of the cutting method in ``Steel Ferrite Grain Size Testing Method'', in which the cut cross section of the sample is polished and corroded, and the corroded surface is observed with a microscope or photographed with a microscope to determine a certain level. The average particle diameter is calculated from the sum of the number and length of carbide particles cut by two line segments whose lengths are perpendicular to each other, using the following formula.

なお、線分の両端にあって一部分しか切断されない硬質
粒子は、その一方だけを数え、切断されない硬質粒子が
線分の一端だけの場合には、これを数えないこととする
。また、一本の線分で切断される硬質粒子の数は、−視
野で少なくとも１０個以上になる様に顕微鏡の倍率を選
定し、総計５０個以上になる様に複数視野測定する。In addition, if the hard particles are located at both ends of a line segment and are only partially cut, only one of them is counted, and if the hard particles that are not cut are only at one end of the line segment, they are not counted. In addition, the magnification of the microscope is selected so that the number of hard particles cut by one line segment is at least 10 in a negative field of view, and the measurement is performed in multiple fields so that the total number of hard particles is 50 or more.

測定例：　第１図によれば、 平均粒子径＝ｄ　＋０　°°゛＋０　　となる・■硬質
相の平均粒子間隔：前記０項に順じ、一定の長さの直交
する二本の線分で切断される隣接硬質粒子相互の間隔長
の平均値を次式によって求める。Measurement example: According to Figure 1, average particle diameter = d + 0 °°゛ + 0 - Average particle spacing of hard phase: Two orthogonal line segments of constant length according to the above 0 term The average value of the distance between adjacent hard particles cut by is determined by the following formula.

、、−ｔｙ）＝平均粒子間隔 粒子間の数 なお、線分の両端がそれぞれ硬質粒子の一部分を切断す
る場合には、一方の硬質粒子についてのみ、その隣接粒
子との間の長さを勘定し、線分の一端だけが硬質粒子の
一部分を切断する場合には、その隣接粒子との間の長さ
を勘定に入れないこととする。また、一本の線分で切断
される硬質粒子相互の間隔部分の数は、−視野で少なく
とも１０以上になる様に顕微鏡の倍率を選定し、総計５
０以上になる様に複数視野測定する。,, -ty)=Average particle spacing between particlesIf both ends of the line segment each cut a part of a hard particle, consider the length between only one hard particle and its adjacent particle. However, when only one end of a line segment cuts a part of a hard particle, the length between it and the adjacent particle is not taken into account. In addition, the magnification of the microscope is selected so that the number of intervals between hard particles cut by one line segment is at least 10 in the field of view, and the total number of intervals between hard particles is 5.
Measure multiple visual fields so that the value is 0 or more.

測定例：　第１図によれば、 平均粒子間隔＝ｆＪ　　−１＋°°°１　　となる。Measurement example: According to Figure 1, Average particle spacing=fJ-1+°°°1.

■硬質相の恒（視野占有面積率）：試料の切断断面を研
磨仕上げして腐蝕し、腐蝕面を顕微鏡写真に撮影して、
第２図に示す線分法により視野占有面積率を求める。■Constancy of hard phase (view area ratio): The cut section of the sample is polished and corroded, and the corroded surface is photographed with a microscope.
The visual field occupation area ratio is determined by the line segment method shown in FIG.

一定面積の矩形の視野を定め、硬質粒子の大きさに見合
う所定間隔長（ｄ・）で、平行な走査線１を引き、各硬
質粒子２との交線の長さを’ｉｎｊ！、、・・・りｎと
し、走査線１の長さをＬとして、次式により視野占有面
積率を求める。A rectangular field of view with a constant area is determined, parallel scanning lines 1 are drawn at a predetermined interval length (d) corresponding to the size of the hard particles, and the length of the line of intersection with each hard particle 2 is determined by 'inj! , . . . where n is the length of the scanning line 1 and L is the length of the scanning line 1, the visual field occupation area ratio is determined by the following formula.

＝視野占有面積率 （ただし、ｍは走査ｌｉｔの本数である。）なお、この
手法は、画像解析装置によって実行することも可能であ
る。= Visual field occupation area ratio (where m is the number of scan lits). Note that this method can also be executed by an image analysis device.

仄ＪＬＪ ロッカアームの対カム摺接面部に貼着される部片（以下
、対カム摺接部片と称する）、およびカムを、下記■、
■の方法で用意した。组JLJ The piece attached to the cam-to-cam sliding contact surface of the rocker arm (hereinafter referred to as the cam-to-cam sliding contact part) and the cam are as follows:
Prepared using method ■.

■対カム摺接部片の目標組成を、 （以上、いずれも重量％） とし、２５０〜３５０メツシユの粉末が１５〜２５体積
％含まれるＦｅ　−Ｃ−Ｃｒ　−Ｍｏ　−Ｗ−Ｖ−Ｍｎ
　−８Ｌ合金粉末に、Ｃ，Ｆｅ−Ｎ＝金合金Ｆｅ−Ｐ合
金の各粉末を添加、ｆｌ￥！合して圧搾成形した後、真
空炉中にて、温度１１９５℃１時間６０分なる条件で焼
結を行なった。■The target composition of the sliding contact piece for the cam is Fe-C-Cr-Mo-W-V-Mn containing 15 to 25 volume % of 250 to 350 mesh powder.
-Add C, Fe-N = gold alloy Fe-P alloy powder to 8L alloy powder, fl\! After the mixture was pressed and molded, sintering was performed in a vacuum furnace at a temperature of 1195° C. for 1 hour and 60 minutes.

次に、焼結晶をロッカアームの対カム贋接面部にろう付
けした後、浸炭焼入れ、焼戻しを行い、研磨して対カム
摺接部片Ａを得た。Next, the sintered crystal was brazed to the surface of the rocker arm that was in contact with the cam, and then carburized and quenched, tempered, and polished to obtain a piece A that was in sliding contact with the cam.

また、焼結晶をロッカアームの対カム摺接面部にろう付
けした後、浸炭焼入れ、焼戻しを行い、研磨して、更に
塩浴軟窒化処Ｉ！！（温度５８０℃１時間１０分）を施
して対カム摺接部片８を得た。In addition, after brazing the sintered crystal to the sliding surface of the rocker arm against the cam, carburizing, quenching, tempering, polishing, and salt bath nitrocarburizing treatment I! ! (Temperature: 580° C. for 1 hour and 10 minutes) to obtain a sliding contact piece 8 for the cam.

対カム摺接部片Ａの基地相の硬度はＦＩＶ　６００〜９
００　、　炭化物１４　Ｉｆ　ハｌｌＶ　１，０００〜
１，３００　、密度は７．６５〜７．７０ｇ／α３であ
った。The hardness of the base phase of the sliding contact piece A for the cam is FIV 600-9
00, Carbide 14 If Hal V 1,000~
1,300, and the density was 7.65 to 7.70 g/α3.

また、前記測定方法によって摺動部材における炭化物存
在状態を調べたところ、平均粒子径４．５μｍ、平均粒
子間隔１１μｍ、視野占有面積率３０％であった。Further, when the presence of carbides in the sliding member was investigated using the above-mentioned measuring method, the average particle diameter was 4.5 μm, the average particle spacing was 11 μm, and the visual field occupation area ratio was 30%.

なお、焼結および熱処理によって得た摺動部材は、マル
テンサイトおよびベイナイトの塩浴軟窒化処理による拡
散層基地相に硬質な金属炭化物を分散させたものであり
、自身の耐摩耗性向上を計るとともに、炭化物の種類、
聞、大きさ１分散状態の適切な選択によって相手材であ
るカムの摩耗を少なくすることができる。The sliding member obtained by sintering and heat treatment has hard metal carbide dispersed in the base phase of the diffusion layer obtained by martensite and bainite salt bath nitrocarburizing treatment, and is designed to improve its own wear resistance. Along with the type of carbide,
However, by appropriately selecting the size 1 dispersion state, wear on the cam, which is the mating material, can be reduced.

各元素の添加理由は下記の通りである。The reasons for adding each element are as follows.

Ｃｒは、基地相を強化すると共に、Ｃと反応して硬質の
炭化物を形成し、耐摩耗性を向上させる。Cr not only strengthens the base phase but also reacts with C to form a hard carbide, improving wear resistance.

ただし、その添加量が５重〜％未満では所要の効果を期
待できず、３０重量％を越えて添加すると、相手カムを
摩耗させ易くなり総合摩耗量が大きくなる他、焼結性が
著しく低下する等の不利を生じる。However, if the amount added is less than 5% by weight, the desired effect cannot be expected, and if it is added in excess of 30% by weight, the mating cam will be likely to wear out, the total amount of wear will increase, and the sinterability will decrease significantly. This may result in disadvantages such as

ＭＯは、ｃｒと同様に基地相を強化すると共に、Ｃと反
応して硬質の炭化物を形成し、耐摩耗性を向上させる。Like Cr, MO strengthens the base phase and reacts with C to form hard carbide, thereby improving wear resistance.

ただし、添加量１重８％未満では所望の効果が得られず
、５重量％を越えて添加すると材料の脆化を招く。However, if the amount added is less than 8% by weight, the desired effect cannot be obtained, and if it is added in excess of 5% by weight, the material becomes brittle.

Ｗ、■は、いずれもＣと反応してＭＣ型（ただし、Ｍは
金属元素記号を示す）の硬質炭化物を形成し、耐摩耗性
の向上に寄与する。両者のうち少なくとも１種の成分の
添加量が０．１重量％以上でなければ所望の効果が得ら
れず、添加９４重量％を越えると切削性が低下し、また
相手材を摩耗させ易くなる。Both W and ■ react with C to form an MC type (where M represents a metal element symbol) hard carbide, contributing to improvement in wear resistance. The desired effect cannot be obtained unless the amount of at least one of the two components added is 0.1% by weight or more, and if the amount exceeds 94% by weight, the machinability decreases and the mating material is likely to wear out. .

Ｓｎは、基地相中に拡散固溶し、Ｎλによるオーステナ
イト化を抑制する作用がある。添加量が０．２ｍｍ％未
満では効果が認められず、５重量％より多く添加すると
炭化物粒子を粗大化させ、機械的強度を低下させて耐摩
耗性が悪化する。Sn diffuses into the base phase as a solid solution and has the effect of suppressing austenitization due to Nλ. If the amount added is less than 0.2 mm%, no effect will be observed, and if it is added more than 5% by weight, the carbide particles will become coarse, mechanical strength will be reduced, and wear resistance will deteriorate.

Ｎλは、基地相を強化し炭化物の脱落を防止する。また
、焼結性を向上させ、相手カムとのなじみ性を良くする
作用をも有する。さらに、３ｎを伴わずに５１ｍ％を越
えて添加すると、基地相中にオーステナイト相が生じ、
耐摩耗性が低下するが、８０世が上述の範囲においては
、Ｎλ５，５〜１０重量％の添加量で良好な耐摩耗性を
示す。Nλ strengthens the base phase and prevents carbide from falling off. It also has the effect of improving sinterability and improving compatibility with the mating cam. Furthermore, if more than 51 m% is added without 3n, an austenite phase will occur in the base phase,
Although the abrasion resistance decreases, when the 80th grade is in the above range, good abrasion resistance is exhibited at an addition amount of Nλ of 5.5 to 10% by weight.

Ｃは、基地相を強化すると共に、Ｃｒ、その他の添加成
分と反応して硬質相を析出させ、耐摩耗性を向上させる
。ただし、１重量％未満では所望の効果が得られず、４
重量％を越えると靭性の低下を招く。C strengthens the base phase, reacts with Cr and other additive components, precipitates a hard phase, and improves wear resistance. However, if it is less than 1% by weight, the desired effect cannot be obtained;
Exceeding this percentage by weight results in a decrease in toughness.

Ｐ、Ｂは、焼結を促進させる作用を有し、焼結部材を高
密度化させる元素であり、少なくともその一方を添加す
ればよい。添加量が、０．０５重量％未満では所望の効
果が得られず、５重量％を越えて添加すると、焼結時に
過剰の液相を生じて寸法変化率が大きくなり好ましくな
い。P and B are elements that have the effect of promoting sintering and increase the density of the sintered member, and at least one of them may be added. If the amount added is less than 0.05% by weight, the desired effect cannot be obtained, and if it is added in excess of 5% by weight, an excessive liquid phase is generated during sintering, resulting in a large dimensional change rate, which is not preferable.

■ＪＩＳ　Ｇ５５０１−Ｆｅ１２　（ねずみ鋳鉄）製カ
ムを用意した。このカムは、カム・ノーズを中心にして
±９０度の角度範囲でチル化されており、該カムのカム
・ノーズを中心にして±３０度の角度範囲に亘る表面層
にプラズマ・トーチを用いて深さ１１ＮＲの急速再溶融
処理を施し、その溶融池にＣｒ粉末１．５重１％、ＭＯ
粉粉末１邑邑を添加した後、自己冷却により急冷せしめ
た。得られたカム３を第３図、第４図に示す（図中、４
はカム・ノーズ。■A cam made of JIS G5501-Fe12 (gray cast iron) was prepared. This cam is chilled over an angular range of ±90 degrees around the cam nose, and the surface layer of the cam over an angular range of ±30 degrees around the cam nose is chilled using a plasma torch. Cr powder 1.5wt 1%, MO
After adding one powder, it was rapidly cooled by self-cooling. The obtained cam 3 is shown in FIGS. 3 and 4 (in the figure, 4
is a cam nose.

５はチル層、６は再溶融硬化処理層をそれぞれ示してい
る）。チルＷＪ５の硬度はＨＲＣ４５，再溶融硬化処理
層６の硬度はＨＲｅＯ４であった。5 indicates a chilled layer, and 6 indicates a remelted hardened layer). The hardness of Chill WJ5 was HRC45, and the hardness of remelting hardened layer 6 was HReO4.

なお、再溶融硬化処理の際に溶融池に添加するＣｒ粉末
、ＭＯ粉末は、炭化物安定化元素であって、この他、Ｖ
、Ｎｂも同様な機能を有する。これ等の元素は、その単
体粉末、それ等相互の合金粉末、あるいは炭素等との化
合物粉末形態として添加され得る。ただし、炭化物安定
化元糸の添加量が０．５重量％未満では、再溶融硬化処
理層中の炭化物量が少なくなって耐摩耗性の大幅向上を
期待できず、また、４重Ｒ％を越えて添加しても、耐摩
耗性の向上効果が少なく、経済的に不利となる。Note that the Cr powder and MO powder added to the molten pool during the remelting hardening process are carbide stabilizing elements, and in addition, V
, Nb also have similar functions. These elements can be added in the form of a single powder, an alloy powder of them, or a compound powder with carbon or the like. However, if the amount of carbide-stabilized base yarn added is less than 0.5% by weight, the amount of carbide in the remelt-hardened layer will be too small to expect a significant improvement in wear resistance. Even if it is added in excess, the effect of improving wear resistance will be small and it will be economically disadvantageous.

■前記■項によって得た複数のカム３を用い、また前記
０項と同様の手法で得た炭化物存在状態の異なる複数の
対カム摺接部片Ａを用意し、各対カム店接部片Ａとカム
とを、内燃機関に組み込み、２０００ｒｐｍ、　　３０
０時間の運転を行ない、各組合せについて対カム摺接部
片とカムの摩耗間を調べ、その結果を第５図ないし第７
図に示した。■ Using a plurality of cams 3 obtained in the above section (■), and preparing a plurality of cam sliding contact pieces A with different carbide presence states obtained by the same method as in the above section 0, each cam contact piece A and the cam are incorporated into an internal combustion engine, and the engine speed is 2000 rpm, 30
After 0 hours of operation, the wear between the cam sliding contact piece and the cam was examined for each combination, and the results are shown in Figures 5 to 7.
Shown in the figure.

また、対カム摺接部片Ｂについても同様に内燃１５１ｒ
＠に組み込み、６０００ｒｐｉ、　　４００時間の運転
を行い、その摩耗量を調べ、対カム摺接部片Ａの摩耗量
と対比して第８図に示した。Similarly, regarding the sliding contact piece B for the cam, the internal combustion 151r
It was assembled into a motor and operated for 400 hours at 6,000 rpm, and the amount of wear was examined, and the results are shown in Fig. 8 in comparison with the amount of wear on the sliding contact piece A against the cam.

■第５図は、対カム摺接部片への組織中に含まれる炭化
物の粒子径が摩耗量に及ぼす影響を示している。(2) Figure 5 shows the influence of the particle size of carbides contained in the structure of the sliding contact piece against the cam on the amount of wear.

第５図によれば、炭化物の平均粒子径が１５μｍを越え
るとカムの摩耗量が急増し、平均粒子径４μｍ以下につ
いては、該粒子径の測定が難しく、この範囲で、カムの
摩耗量が増加する傾向がある。According to Figure 5, when the average particle size of carbide exceeds 15 μm, the amount of cam wear increases rapidly, and when the average particle size is 4 μm or less, it is difficult to measure the particle size, and within this range, the amount of cam wear increases. There is a tendency to increase.

また、対カム摺接部片Ａの摩耗量は、炭化物の平均粒子
径が６μｍを越えるとやや増大する傾向があるものの、
はぼ一定である。Furthermore, although the amount of wear on the sliding contact piece A for the cam tends to increase slightly when the average particle diameter of the carbide exceeds 6 μm,
is almost constant.

それ故、カムの摩耗量が７〜２７μｍ、対カム摺接部片
Ａの摩耗量が６〜１７μｍである平均粒子径４〜１５μ
ｍの範囲を選択するのが望ましく、炭化物の８０％以上
が粒子径４〜１５μｍであればその範囲に収まる。Therefore, the average particle diameter is 4 to 15 μm, and the amount of wear on the cam is 7 to 27 μm, and the amount of wear on the sliding contact piece A to the cam is 6 to 17 μm.
It is desirable to select a range of m, and if 80% or more of the carbide has a particle size of 4 to 15 μm, it falls within that range.

■第６図は、対カム摺接部片Ａの組織中に含まれる炭化
物の平均粒子間隔が摩耗３に及ぼす影響を示している。(2) FIG. 6 shows the influence of the average particle spacing of carbides contained in the structure of the piece A in sliding contact with the cam on wear 3.

第６図によれば、炭化物の平均粒子間隔が１５μｍを越
えると対カム摺接部片Ａの摩耗量が増大し、平均粒子間
隔が２０μｍを越えるとカムの摩耗量が増え、スカッフ
現象が生じる。According to FIG. 6, when the average particle spacing of carbide exceeds 15 μm, the amount of wear on the sliding contact piece A for the cam increases, and when the average particle spacing exceeds 20 μm, the amount of wear on the cam increases, causing the scuffing phenomenon. .

また、平均粒子間隔が５μｍ未満では、対カム摺接部片
Ａにおける基地相の強度が低下して割れが発生し、カム
の摩耗色も増加する傾向ζなる。Furthermore, if the average particle spacing is less than 5 μm, the strength of the base phase in the piece A that is in sliding contact with the cam decreases, cracks occur, and the wear color of the cam tends to increase.

それ故、カムの摩耗量が９〜１９μｍ、対カム摺接部片
△の摩耗量が５〜１６μｍである平均粒子間隔５〜１５
μｍの範囲を選択するのが望ましく、さらに望ましい平
均粒子間隔は５〜１２μｍである。Therefore, the average particle spacing is 5 to 15 μm, and the wear amount of the cam is 9 to 19 μm, and the wear amount of the sliding contact piece △ to the cam is 5 to 16 μm.
It is desirable to select a range of .mu.m, and more preferably the average particle spacing is 5 to 12 .mu.m.

■第７図は、対カム摺接部片への組織中に含まれる炭化
物の視野占有面積率が摩耗量に及ぼす影響を示しており
、また第８図は、炭化物視野占有面積率と摺動部材（対
カム摺接部片Ａ、Ｂ）の摩耗量との関係を対比して示し
ている。■Figure 7 shows the effect of the area ratio of carbide in the visual field on the structure of the sliding contact piece against the cam on the amount of wear, and Figure 8 shows the effect of the area ratio of carbide in the visual field and the sliding contact area of the carbide. The relationship between the amount of wear of the members (the cam sliding contact pieces A and B) is shown in comparison.

第７図、第８図によれば、視野占有面積率が大きくなる
ほど、カムの摩耗（支）がほぼ直線的に増大し、対カム
摺接部片の摩耗ｍがほぼ直線的に減少することが判る。According to FIGS. 7 and 8, as the visual field occupation area ratio increases, the wear (support) of the cam increases almost linearly, and the wear m of the sliding contact piece against the cam decreases almost linearly. I understand.

また、視野占有面積率が５０％を越えると、カムの摩耗
が増大するにもかかわらず、対カム摺接部片の摩耗ｍは
ほとんど変化しなくなり、かつ割れが生じ易いため、視
野占有面積率５０％以下にするのが望ましい。そして、
視野占有面積率１０％未満では炭化物による効果を期待
できないため、視野占有面積率１０％以上にすべきであ
る。Furthermore, when the field of view area ratio exceeds 50%, even though the wear of the cam increases, the wear m of the sliding contact piece against the cam hardly changes, and cracks are likely to occur. It is desirable to keep it below 50%. and,
If the visual field occupation area ratio is less than 10%, the effect of carbides cannot be expected, so the visual field occupation area ratio should be 10% or more.

それ故、カムの摩耗分が１′２〜１４．４μｍ、対カム
摺接部片の摩耗量が３．７〜１１．０μｍである視野占
有面積率１０〜５０％の範囲を選択するのが望ましい。Therefore, it is best to select a field area ratio of 10 to 50% in which the wear amount of the cam is 1'2 to 14.4 μm and the amount of wear of the sliding contact piece to the cam is 3.7 to 11.0 μm. desirable.

また、塩浴軟窒化処理を施すことにより、摩耗６を更に
低減化することができる。In addition, by performing salt bath nitrocarburizing treatment, wear 6 can be further reduced.

ｌ叫五１浬 以上の説明から明らかな様に、少なくともその摺動表面
層が基地相中に硬質相が分散した金属組織体として形成
された第−摺動部材と、これに摺接する鉄系金属製第二
摺動部材との組合せであって、第一摺動部材の基地相中
に平均粒子間隔５〜１５μｍ、視野占有面積率１０〜５
０％で分散した硬質相の８０％以上を大きさ４〜１５μ
ｍの粒子が占めており、第二摺動部材は、その摺動表面
層に高密度エネルギー照射による再溶融硬化処理が施さ
れていることを特徴とする摺動部材の組合せが提案され
た。As is clear from the above explanation, there is a first sliding member whose sliding surface layer is formed as a metal structure in which a hard phase is dispersed in a base phase, and an iron-based sliding member that is in sliding contact with the sliding member. A combination with a second sliding member made of metal, wherein the base phase of the first sliding member has an average particle spacing of 5 to 15 μm and a visual field occupation area ratio of 10 to 5.
At least 80% of the hard phase dispersed at 0% is 4 to 15 μm in size.
A combination of sliding members has been proposed, characterized in that the second sliding member has its sliding surface layer subjected to remelting hardening treatment by high-density energy irradiation.

斯かる組合せによれば、第一摺動部材の金Ｒ組織中に含
まれ該第−摺動部材の耐摩耗性を向上させるとともに、
第二摺動部材の摩耗量を左右する硬質相の大きさ２分散
状態が、実験的に求められた最適値に規定されているた
め、両店動部材の摩耗量が十分少なく、動力機械用摺動
部材の組合せとして優れた耐久性を発揮し得る。According to such a combination, gold is contained in the R structure of the first sliding member and improves the wear resistance of the first sliding member,
The size and dispersion state of the hard phase, which determines the amount of wear on the second sliding member, is set to the optimum value determined experimentally, so the amount of wear on both sliding members is sufficiently small, making it ideal for power machinery. Excellent durability can be demonstrated as a combination of sliding members.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は合金基地相中に含まれる炭化物の平均粒子径を
測定する方法を示す図、第２図は同じく平均粒子間隔離
を測定する方法を示す図、第３図はその表面に再溶Ｆｌ
ｉ硬化処理を施された鋳鉄製カムの断面図、第４図はそ
のＩＶ−ＩＶ線断面図、第５図は炭化物平均粒子径と、
カム、対カム摺接部片Ａの摩耗量との関係を示すグラフ
、第６図は炭化物平均粒子間隔と、カム、対カム虐接部
片Ａの摩耗量との関係を示すグラフ、第７図は炭化物の
視野占有面積率と、カム、対カム摺接部片Ａの摩耗量と
の関係を示すグラフ、第８図は炭化物の視野占有面積率
と、カム、対カム贋接部片Ａ、Ｂとの関係を対比的に示
すグラフである。 １・・・走査線、２・・・炭化物粒子、３・・・カム、
４・・・カム・ノーズ、５・・・チル層、６・・・再溶
融硬化処理層。Figure 1 shows a method for measuring the average grain size of carbides contained in the alloy matrix phase, Figure 2 shows a method for measuring the average interparticle separation, and Figure 3 shows how to measure the average grain size of carbides contained in the alloy base phase. Fl
A cross-sectional view of a cast iron cam that has been subjected to i-hardening treatment, FIG. 4 is a cross-sectional view taken along the line IV-IV, and FIG.
Figure 6 is a graph showing the relationship between the wear amount of the cam and the piece A that comes into sliding contact with the cam. The figure is a graph showing the relationship between the visual field occupation area ratio of carbide and the amount of wear of the cam and the sliding contact piece A of the cam. Figure 8 is the graph showing the relationship between the visual field occupation area ratio of carbide and the cam and the counterfeit contact piece A of the cam. , B in contrast. 1... Scanning line, 2... Carbide particles, 3... Cam,
4... Cam nose, 5... Chill layer, 6... Remelting hardening treatment layer.

Claims (3)

【特許請求の範囲】[Claims] （１）少なくともその摺動表面層が基地相中に硬質相が
分散した金属組織体として形成された第一摺動部材と、
これに摺接する鉄系金属製第二摺動部材との組合せにお
いて、 第一摺動部材の硬質相は、その８０％以上が大きさ４〜
１５μｍの粒子であって、平均粒子間隔５〜１５μｍ、
視野占有面積率１０〜５０％で分散しており、第二摺動
部材は、その摺動表面層に高密度エネルギー照射による
再溶融硬化処理が施されていることを特徴とする摺動部
材の組合せ。(1) a first sliding member in which at least the sliding surface layer is formed as a metal structure in which a hard phase is dispersed in a base phase;
In combination with a second sliding member made of iron-based metal that is in sliding contact with this, 80% or more of the hard phase of the first sliding member has a size of 4 to 4.
15 μm particles, with an average particle spacing of 5 to 15 μm;
The second sliding member is dispersed at a viewing area ratio of 10 to 50%, and the second sliding member has its sliding surface layer subjected to remelting hardening treatment by high-density energy irradiation. combination. （２）前記第二摺動部材の摺動表面層には、再溶融硬化
処理を施す際に、Ｃｒ、Ｍｏ、Ｖ、およびＮｂより成る
群から選択される少なくとも一種の炭化物安定化元素が
強制添加されていることを特徴とする特許請求の範囲第
１項に記載された摺動部材の組合せ。(2) At least one carbide stabilizing element selected from the group consisting of Cr, Mo, V, and Nb is forcibly added to the sliding surface layer of the second sliding member during remelting hardening treatment. A combination of sliding members according to claim 1, characterized in that the combination of sliding members is added. （３）前記第一摺動部材が、内燃機関の動弁機構で用い
られるロッカアームの対カム摺接面に付設される耐摩耗
部片であり、前記第二摺動部材が、前記耐摩耗部片と対
をなすカムであることを特徴とする特許請求の範囲第１
項または第２項に記載された摺動部材の組合せ。(3) The first sliding member is a wear-resistant piece attached to a cam sliding surface of a rocker arm used in a valve mechanism of an internal combustion engine, and the second sliding member is a wear-resistant piece attached to a cam sliding surface of a rocker arm used in a valve mechanism of an internal combustion engine. Claim 1 characterized in that the cam is a pair of cams.
A combination of the sliding members described in item 1 or 2.