JPH0972342A - Rolling bearing member - Google Patents
Rolling bearing memberInfo
- Publication number
- JPH0972342A JPH0972342A JP22827795A JP22827795A JPH0972342A JP H0972342 A JPH0972342 A JP H0972342A JP 22827795 A JP22827795 A JP 22827795A JP 22827795 A JP22827795 A JP 22827795A JP H0972342 A JPH0972342 A JP H0972342A
- Authority
- JP
- Japan
- Prior art keywords
- rolling
- carbide
- cementation
- environment
- particle size
- 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.)
- Withdrawn
Links
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は優れた転動疲労性を
有するころがり軸受部材に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling bearing member having excellent rolling contact fatigue resistance.
【０００２】[0002]
【従来の技術】従来、各種産業機械に用いられる軸受
は、ＪＩＳ Ｇ ４８０５に規定される高炭素クロム軸
受鋼材に球状化焼鈍を施した後、球状炭化物を残したま
ま基地組織をオーステナイト温度域まで加熱し焼入れ・
焼もどしを施すことによって、マルテンサイト組織に数
％の残留オーステナイトと残存炭化物が分散する組織に
処理されていた。2. Description of the Related Art Conventionally, bearings used in various industrial machines have been manufactured by subjecting a high carbon chromium bearing steel material specified in JIS G 4805 to spheroidizing annealing, and then leaving the matrix structure in the austenite temperature range while leaving spherical carbides. Heated and quenched
By carrying out tempering, the martensite structure was treated to a structure in which a few% of retained austenite and residual carbide were dispersed.
【０００３】しかしながら、上記の処理方法で製造され
た軸受では、使用時に周辺部品の金属磨耗粉、バリ、外
来系の硬質な異物などが混入する環境下においては、そ
れらを含まない環境下での寿命に比べて転動疲労寿命が
大きく低下するという問題があった。However, in the bearing manufactured by the above-mentioned processing method, in the environment where metal abrasion powder, burrs, foreign hard foreign matters, etc. of peripheral parts are mixed during use, the bearing is not included in the environment. There is a problem that the rolling contact fatigue life is much shorter than the life.
【０００４】そこで、特開平４−２６７５２号の公報に
は、低合金鋼に浸炭または浸炭窒化処理を施すことによ
り、軸受部材の最表層に残留オースナイトを多量に生成
させ、かつ平均粒径０．５〜１．５μｍの炭化物または
炭窒化物を析出させることにより表面硬度を高くし、異
物が混入した使用環境下での転動疲労寿命を向上させる
技術が開示されている。しかしながら、低合金鋼は素材
の炭素含有量が少ないために、所望する残留オーステナ
イト量および微細炭化物あるいは炭窒化物を析出させる
のに必要な炭素量を得るには、浸炭または浸炭窒化処理
を長時間（約４〜１０時間）施す必要があり、省エネル
ギーや製造コスト低減の観点から、浸炭または浸炭窒化
を短時間で行うことができ、しかも異物が混入した使用
環境下でも優れた転動疲労性を有するころがり軸受部材
の開発が要望されている。In view of this, Japanese Patent Laid-Open No. 4-26752 discloses that a low alloy steel is carburized or carbonitrided to produce a large amount of residual austenite in the outermost surface layer of a bearing member and has an average grain size of 0. There is disclosed a technique of increasing the surface hardness by precipitating carbides or carbonitrides of 0.5 to 1.5 μm to improve the rolling fatigue life in a use environment in which foreign matter is mixed. However, since the low alloy steel has a low carbon content in the material, in order to obtain the desired residual austenite amount and the amount of carbon necessary for precipitating fine carbides or carbonitrides, carburizing or carbonitriding treatment is performed for a long time. (About 4 to 10 hours), carburizing or carbonitriding can be performed in a short time from the viewpoint of energy saving and manufacturing cost reduction, and excellent rolling fatigue resistance is obtained even in a use environment in which foreign matter is mixed. The development of the rolling bearing member has been demanded.
【０００５】[0005]
【発明が解決しようとする課題】本発明は上記事情に着
目してなされたものであって、その目的は、従来の高炭
素クロム鋼材により製造された軸受よりも異物が混入し
た使用環境下でも優れた転動疲労性を発揮し、かつ低合
金鋼より浸炭または浸炭窒化時間の短縮を図ることがで
きるころがり軸受部材を提供することにある。SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and its purpose is even in a use environment in which foreign matter is mixed in compared with a bearing manufactured by a conventional high carbon chromium steel material. It is an object of the present invention to provide a rolling bearing member that exhibits excellent rolling contact fatigue resistance and that can reduce the carburizing or carbonitriding time compared to low alloy steel.
【０００６】[0006]
【課題を解決するための手段】上記目的を達成した本発
明に係るころがり軸受部材とは、ころがり軸受部材にお
ける軌道輪および転動体の少なくとも１つは、高炭素ク
ロム軸受鋼を浸炭または浸炭窒化した後、焼入れ・焼も
どしを施したものであり、該軌道輪及び／又は転動体の
最表層における残留オーステナイト量が１０〜５０ｖｏ
ｌ％、上記軌道輪及び／又は転動体の最表層に含有され
る平均粒径０．５μｍ以下の炭化物または炭窒化物の面
積率／平均粒径が４％／μｍ以上の範囲にあることを要
旨とするものである。尚、浸炭または浸炭窒化と、焼入
れ・焼もどしの間で、Ａｃ1 点以下の温度まで冷却後再
度加熱することが推奨される。According to the rolling bearing member of the present invention which has achieved the above object, at least one of a bearing ring and a rolling element in the rolling bearing member is formed by carburizing or carbonitriding high carbon chromium bearing steel. After that, the amount of retained austenite in the outermost surface layer of the bearing ring and / or the rolling element is 10 to 50 vo after quenching and tempering.
1%, the area ratio / average particle size of carbides or carbonitrides having an average particle size of 0.5 μm or less contained in the outermost layer of the bearing ring and / or the rolling element is in the range of 4% / μm or more. It is a summary. In addition, it is recommended to reheat after cooling to a temperature of Ac 1 point or less between carburizing or carbonitriding and quenching / tempering.
【０００７】[0007]
【発明の実施の形態】本発明者らは、従来の高炭素クロ
ム軸受鋼材で多量の残留オーステナイトを析出させ、か
つ軟質な残留オーステナイトが増えても高い表面硬度が
得られるころがり軸受部材について検討してきた。BEST MODE FOR CARRYING OUT THE INVENTION The present inventors have investigated a rolling bearing member which is capable of precipitating a large amount of retained austenite in a conventional high carbon chromium bearing steel material and obtaining high surface hardness even if the amount of soft retained austenite increases. It was
【０００８】その結果、高炭素クロム鋼材に浸炭または
浸炭窒化を施して、当該表層部にＣを侵入させて基地中
の炭素濃度を従来より高めることにより焼入れ・焼きも
どし後の残留オーステナイトを増加させ、その生成量を
１０〜５０ｖｏｌ％にすると共に、平均粒径０．５μｍ
以下の炭化物または炭窒化物を析出させ、該炭化物また
は炭窒化物の面積率と平均粒径の比（面積率／平均粒
径）を４％／μｍ以上に制御すれば、軟質な残留オース
テナイトが多数生成しても、微細析出物の分散強化作用
により高い表面硬度が得られ、異物が混入した使用環境
下での転動疲労寿命が飛躍的に向上することを見出し
た。As a result, by carburizing or carbonitriding the high carbon chromium steel material, C is introduced into the surface layer portion to increase the carbon concentration in the base as compared with the conventional case, thereby increasing the retained austenite after quenching and tempering. , The production amount is 10 to 50 vol%, and the average particle size is 0.5 μm.
When the following carbides or carbonitrides are deposited and the ratio of the area ratio of the carbides or carbonitrides to the average particle size (area ratio / average particle size) is controlled to 4% / μm or more, soft residual austenite is formed. It has been found that even if a large number of particles are formed, a high surface hardness is obtained due to the dispersion strengthening action of fine precipitates, and the rolling fatigue life is dramatically improved in a use environment in which foreign matter is mixed.
【０００９】また、浸炭または浸炭窒化と、焼入れ・焼
もどしの間でを施した後、Ａｃ1 点以下の温度まで冷却
後再度加熱することにより、平均粒径０．５μｍ以下の
微細な炭化物または炭窒化物の析出量がさらに多くなる
ので、上記面積率／平均粒径を高くでき、異物が混入し
た使用環境下での転動疲労寿命を向上させることができ
る。Further, after carrying out between carburizing or carbonitriding and quenching / tempering, by cooling to a temperature of Ac 1 point or less and then heating again, fine carbides having an average particle size of 0.5 μm or less or Since the amount of carbonitrides deposited is further increased, the above-mentioned area ratio / average particle diameter can be increased, and rolling fatigue life in a use environment in which foreign matter is mixed can be improved.
【００１０】本発明に係るころがり軸受部材において、
数値限定を行った理由について以下に述べる。 ・最表層の残留オーステナイト量：１０〜５０ｖｏｌ％ 異物が混入した使用環境下においては、転動中に異物と
繰り返し接触することにより内外輪の転動面に圧痕が発
生するが、残留オーステナイトはその圧痕から亀裂が発
生したり亀裂が進展することを抑制する効果がある。残
留オーステナイト量が１０ｖｏｌ％未満ではこのような
効果は少なく、また、５０ｖｏｌ％を超えると逆に硬さ
が低下し圧痕が発生しやすくなり、しかも寸法安定性が
劣化する。従って、本発明に係るころがり軸受部材では
残留オーステナイト量を１０〜５０ｖｏｌ％に設定し
た。尚、２０〜４０ｖｏｌ％が好ましい範囲である。In the rolling bearing member according to the present invention,
The reason for limiting the numerical values will be described below.・ Amount of retained austenite in the outermost layer: 10 to 50 vol% In a use environment in which foreign matter is mixed, indentations are generated on the rolling surfaces of the inner and outer races due to repeated contact with the foreign matter during rolling. It has the effect of suppressing the occurrence of cracks and the development of cracks from the indentations. When the amount of retained austenite is less than 10 vol%, such an effect is small, and when it exceeds 50 vol%, the hardness is decreased to the extent that indentation is likely to occur and the dimensional stability is deteriorated. Therefore, in the rolling bearing member according to the present invention, the amount of retained austenite is set to 10 to 50% by volume. 20 to 40 vol% is a preferable range.
【００１１】・最表層での平均粒径０．５μｍ以下の炭
化物または炭窒化物の面積率／平均粒径：４％／μｍ以
上 炭化物または炭窒化物は、基地への析出による分散強化
で硬さを向上させ、軟質な残留オーステナイトを増量さ
せたことによる硬さの低下分を補うことができ、ころが
り軸受部材として高い表面硬度を得ることができる。こ
のことにより異物が混入した使用環境下において使用中
に異物と繰り返し接触することにより内外輪の転動面に
発生する圧痕を抑制することができる。即ち、異物が混
入した使用環境下での転動疲労寿命を向上させる。その
ためには、平均粒径０．５μｍ以下の炭化物または炭窒
化物の面積率／平均粒径を４％／μｍ以上にする必要が
あり、５％／μｍ以上あると好ましい。Area ratio of carbides or carbonitrides having an average particle size of 0.5 μm or less in the outermost layer / average particle size: 4% / μm or more Carbides or carbonitrides are hardened by dispersion strengthening due to precipitation on the matrix. The hardness can be improved and the decrease in hardness due to the increase in the amount of soft retained austenite can be compensated for, and a high surface hardness can be obtained as the rolling bearing member. As a result, it is possible to suppress the indentation generated on the rolling surfaces of the inner and outer races due to repeated contact with the foreign matter during use in a use environment in which the foreign matter is mixed. That is, the rolling fatigue life in a use environment in which foreign matter is mixed is improved. For that purpose, the area ratio of the carbide or carbonitride having an average particle size of 0.5 μm or less / average particle size needs to be 4% / μm or more, and preferably 5% / μm or more.
【００１２】尚、本発明に係るころがり軸受部材は、Ｊ
ＩＳ Ｇ ４８０５に規定される高炭素クロム軸受鋼材
を用いて製造すればよいが、ＣｒやＭｏを増量して添加
することにより異物が混入した使用環境下において転動
疲労寿命がさらに向上することが期待できる。The rolling bearing member according to the present invention is J
It may be manufactured using a high carbon chromium bearing steel material specified in IS G 4805, but by adding Cr and Mo in an increased amount, rolling fatigue life can be further improved in a use environment in which foreign matter is mixed. Can be expected.
【００１３】即ち、Ｃｒ及びＭｏは、浸炭または浸炭窒
化処理による炭化物または炭窒化物の析出量を増加させ
る元素であり、高炭素クロム軸受鋼材に増量添加するこ
とで炭化物の析出量が増加し、最表層の硬さを高め、異
物が混入した使用環境下での転動疲労寿命がさらに向上
する。但し、多過ぎると加工性が低下する。したがっ
て、Ｃｒ含有量は３．５０ｗｔ％以下、Ｍｏ含有量は
１．０ｗｔ％以下とすることが好ましく、より好ましい
Ｃｒ含有量は２．００〜３．５０ｗｔ％、より好ましい
Ｍｏ含有量は０．３０〜０．９０ｗｔ％である。さら
に、上記高炭素クロム軸受鋼材にＷ，Ｖ，Ｎｂを添加し
ても、異物が混入した使用環境下における転動疲労寿命
は向上する。That is, Cr and Mo are elements that increase the precipitation amount of carbides or carbonitrides due to carburizing or carbonitriding treatment, and by increasing the addition amount to the high carbon chromium bearing steel material, the precipitation amount of carbides increases. The hardness of the outermost layer is increased, and the rolling fatigue life is further improved in a usage environment in which foreign matter is mixed. However, if the amount is too large, the workability deteriorates. Therefore, it is preferable that the Cr content is 3.50 wt% or less and the Mo content is 1.0 wt% or less, the more preferable Cr content is 2.00 to 3.50 wt%, and the more preferable Mo content is 0. It is 30 to 0.90 wt%. Further, even if W, V, and Nb are added to the high carbon chromium bearing steel material, the rolling fatigue life in a use environment in which foreign matter is mixed is improved.
【００１４】ＷはＣｒ及びＭｏと同様に浸炭または浸炭
窒化処理により炭化物または炭窒化物の析出量を増加さ
せる元素であり、高炭素クロム軸受鋼材に添加すること
で炭化物の析出量が増加し、当該最表層の硬さをより高
め、異物が混入した使用環境下での転動疲労寿命がさら
に向上する。但し、Ｗ含有量が０．０５ｗｔ％未満では
効果が十分発揮されず、また１．０ｗｔ％を超えると加
工性に悪影響を及ぼす。従って、Ｗ含有量は０．０５〜
１．０ｗｔ％とすることが好ましい。Similar to Cr and Mo, W is an element that increases the precipitation amount of carbides or carbonitrides by carburizing or carbonitriding treatment, and when added to high carbon chromium bearing steel, the precipitation amount of carbides increases. The hardness of the outermost layer is further increased, and the rolling fatigue life in a use environment in which foreign matter is mixed is further improved. However, if the W content is less than 0.05 wt%, the effect is not sufficiently exhibited, and if it exceeds 1.0 wt%, the workability is adversely affected. Therefore, the W content is 0.05 to
It is preferably 1.0 wt%.
【００１５】Ｖ，Ｎｂは、鋼中のＣ，Ｎと結合して炭化
物または炭窒化物を生成し結晶粒を微細化させ、また炭
化物あるいは炭窒化物を微細化させる元素である。高炭
素クロム軸受鋼材に添加することで異物が混入した使用
環境下での転動疲労寿命がさらに向上する。Ｖ含有量が
０．０３ｗｔ％未満、Ｎｂ含有量が０．００５ｗｔ％未
満ではこの様な効果は小さく、多過ぎても効果は飽和す
るので、Ｖ含有量は０．０３〜１．００ｗｔ％、Ｎｂ含
有量は０．００５〜０．５０ｗｔ％とすることが望まし
い。V and Nb are elements that combine with C and N in steel to form carbides or carbonitrides to refine the crystal grains, and to refine the carbides or carbonitrides. Addition to high carbon chrome bearing steel further improves rolling fatigue life in a usage environment in which foreign matter is mixed. If the V content is less than 0.03 wt% and the Nb content is less than 0.005 wt%, such an effect is small, and if the amount is too large, the effect saturates. Therefore, the V content is 0.03 to 1.00 wt%, The Nb content is preferably 0.005 to 0.50 wt%.
【００１６】[0016]
【実施例】表１に成分組成を示す各種の鋼を小型真空炉
において溶製した。[Examples] Various steels having the compositions shown in Table 1 were melted in a small vacuum furnace.
【００１７】[0017]
【表１】 [Table 1]
【００１８】鋼Ｎｏ．１〜５はＪＩＳ Ｇ ４８０５に
規定される高炭素クロム軸受鋼材であり、鋼Ｎｏ．６〜
１５はＪＩＳ Ｇ ４８０５のＳＵＪ２の成分組成にＣ
ｒまたはＭｏが増量して添加されているか、或いはＷ，
Ｖ，Ｎｂが添加された鋼である。これらの鋼にソーキン
グ処理を施し巨大炭化物の拡散消失処理を施した後、熱
間鍛造によりφ６５ｍｍの丸棒に鍛伸し、球状化焼鈍を
施した。続いてφ６０ｍｍ×５t の試験片に加工し、表
２に示す硬化熱処理を施した後、ラッピング加工し、面
圧４９００ＭＰａの条件で異物が混入した環境下で転動
疲労寿命試験を行った。Steel No. Nos. 1 to 5 are high carbon chromium bearing steel materials specified in JIS G 4805. 6 ~
15 is the component composition of JIS G 4805 SUJ2 and C
r or Mo is added in an increased amount, or W,
It is a steel to which V and Nb are added. After subjecting these steels to a soaking treatment and a diffusion disappearance treatment of giant carbides, a round bar of φ65 mm was forged by hot forging, and spheroidizing annealing was performed. Subsequently, it was processed into a test piece of φ60 mm × 5 t , subjected to the hardening heat treatment shown in Table 2 and then subjected to lapping, and a rolling fatigue life test was conducted under the condition of a surface pressure of 4900 MPa in an environment in which foreign matter was mixed.
【００１９】また、ラッピング加工終了後、最表層の残
留オーステナイト量および炭化物または炭窒化物の性状
を調査した。残留オーステナイト量についてはＸ線回折
法で測定した。炭化物および炭窒化物の性状は、樹脂に
埋め込み鏡面仕上げした後、電子顕微鏡で写真撮影を行
い、その写真をもとにトレーシングを行った後、画像解
析装置により、面積率（％）および平均粒径（μｍ）を
測定し、０．５μｍ以下の炭化物あるいは炭窒化物につ
いての面積率／平均粒径（％／μｍ）を算出した。尚、
電子顕微鏡による観察条件は、倍率：８０００倍，視野
面積：１００μｍ2 ，視野数：３視野で行った。After the lapping process was completed, the amount of retained austenite in the outermost layer and the properties of the carbide or carbonitride were investigated. The amount of retained austenite was measured by the X-ray diffraction method. The properties of carbides and carbonitrides are embedded in resin, mirror-finished, photographed with an electron microscope, tracing is performed based on the photograph, and the area ratio (%) and average are measured by an image analyzer. The particle size (μm) was measured, and the area ratio / average particle size (% / μm) for a carbide or carbonitride of 0.5 μm or less was calculated. still,
The observation conditions with an electron microscope were a magnification: 8000 times, a visual field area: 100 μm 2 , and a visual field number: 3 visual fields.
【００２０】[0020]
【表２】 [Table 2]
【００２１】 〈浸炭・（焼入れ）条件〉 ＊１Ａ：９３０℃×２ｈｒ／油冷（６０〜８０℃） Ｃ．Ｐ．：０．８％ ＊１Ｂ：９３０℃×２ｈｒ Ｃ．Ｐ．：０．８％ ＊２Ａ：９３０℃×２ｈｒ／油冷（６０〜８０℃） Ｃ．Ｐ．：１．２％ ＊２Ｂ：９３０℃×２ｈｒ Ｃ．Ｐ．：１．２％<Carburizing / (Quenching) Conditions> * 1A: 930 ° C. × 2 hr / oil cooling (60 to 80 ° C.) C.I. P. : 0.8% * 1B: 930 ° C. × 2 hr C.I. P. : 0.8% * 2A: 930 ° C x 2 hr / oil cooled (60 to 80 ° C) C.I. P. : 1.2% * 2B: 930 ° C. × 2 hr C.I. P. : 1.2%
【００２２】 〈浸炭窒化・（焼入れ）条件〉 ＊３Ａ：９３０℃×２ｈｒ→８５０℃×１ｈｒ／油冷 Ｃ．Ｐ．：１．０％ ＲＸガス＋アンモニアガス（５ｖｏｌ％） ＊３Ｂ：９３０℃×２ｈｒ→８５０℃×１ｈｒ／油冷 Ｃ．Ｐ．：１．０％ ＲＸガス＋アンモニアガス（５ｖｏｌ％）<Carbonitriding / (Quenching) Conditions> * 3A: 930 ° C. × 2 hr → 850 ° C. × 1 hr / oil-cooled C.I. P. : 1.0% RX gas + ammonia gas (5 vol%) * 3B: 930 ° C. × 2 hrs → 850 ° C. × 1 hr / oil cooling C.I. P. : 1.0% RX gas + ammonia gas (5 vol%)
【００２３】〈再加熱焼入れ条件〉 ＊４ ：８５０℃×１ｈｒ／油冷（６０〜８０℃） 〈焼入れ条件〉 ＊５ ：８４０℃×１ｈｒ／油冷 〈焼もどし条件〉 ＊６ ：１７０℃×１ｈｒ／空冷<Reheating and quenching conditions> * 4: 850 ° C x 1 hr / oil cooling (60-80 ° C) <Quenching conditions> * 5: 840 ° C x 1 hr / oil cooling <tempering conditions> * 6: 170 ° C x 1 hr / air cooling
【００２４】 [0024]
【００２５】これら試験片の異物が混入した環境下での
転動疲労試験結果、残留オーステナイト量測定結果、
０．５μｍ以下の炭化物あるいは炭窒化物の性状測定結
果を表３〜６に、異物が混入した環境下での転動疲労寿
命と０．５μｍ以下の炭化物あるいは炭窒化物について
の面積率／平均粒径および残留オーステナイト量の相関
図１〜５に示す。なお転動疲労寿命についてはＬ10（１
０％累積破損率）を示した。The results of the rolling fatigue test, the measurement results of the amount of retained austenite in the environment in which the foreign matters of these test pieces are mixed,
Tables 3 to 6 show the measurement results of properties of carbides or carbonitrides of 0.5 μm or less, and rolling fatigue life in an environment in which foreign matter is mixed and area ratio / average of carbides or carbonitrides of 0.5 μm or less. Correlation between grain size and amount of retained austenite is shown in FIGS. The rolling fatigue life is L 10 (1
0% cumulative damage rate).
【００２６】[0026]
【表３】 [Table 3]
【００２７】[0027]
【表４】 [Table 4]
【００２８】[0028]
【表５】 [Table 5]
【００２９】[0029]
【表６】 [Table 6]
【００３０】図１は、鋼Ｎｏ．１〜５を浸炭・焼入れ→
焼もどしおよび浸炭窒化・焼入れ→焼きもどしを施した
時の０．５μｍ以下の炭化物あるいは炭窒化物について
の面積率／平均粒径と異物が混入した環境下での転動疲
労寿命の関係を示したものである。FIG. 1 shows steel No. Carburizing and quenching 1 to 5 →
Shows the relationship between the area ratio / average particle size of carbides or carbonitrides of 0.5 μm or less when tempered and carbonitrided / quenched → tempered and the rolling contact fatigue life in an environment containing foreign matter. It is a thing.
【００３１】図２は、鋼Ｎｏ．１〜５を浸炭・焼入れ→
焼もどしおよび浸炭窒化・焼入れ→焼きもどしを施した
時の残留オーステナイト量と異物が混入した環境下での
転動疲労寿命の関係を示したものである。FIG. 2 shows steel No. Carburizing and quenching 1 to 5 →
It shows the relationship between the amount of retained austenite when tempering and carbonitriding / quenching → tempering and the rolling contact fatigue life in an environment in which foreign matter is mixed.
【００３２】図３は、鋼Ｎｏ．１〜５を浸炭→Ａｃ1 点
以下の温度まで冷却→再加熱焼入れ→焼もどしおよび浸
炭窒化→Ａｃ1 点以下の温度まで冷却→再加熱焼入れ→
焼きもどしを施した時の０．５μｍ以下の炭化物あるい
は炭窒化物についての面積率／平均粒径と異物が混入し
た環境下での転動疲労寿命の関係を示したものである。FIG. 3 shows steel No. Carburizing 1 to 5 → cooling to a temperature of Ac 1 point or lower → reheating and quenching → tempering and carbonitriding → cooling to a temperature of Ac 1 point or lower → reheating and quenching →
2 shows the relationship between the area ratio / average particle size of carbides or carbonitrides of 0.5 μm or less when tempered and the rolling fatigue life in an environment containing foreign matter.
【００３３】図４は、鋼Ｎｏ．１〜５を浸炭→Ａｃ1 点
以下の温度まで冷却→再加熱焼入れ→焼もどしおよび浸
炭窒化→Ａｃ1 点以下の温度まで冷却→再加熱焼入れ→
焼きもどしを施した時の残留オーステナイト量と異物が
混入した環境下での転動疲労寿命の関係を示したもので
ある。FIG. 4 shows steel No. Carburizing 1 to 5 → cooling to a temperature of Ac 1 point or lower → reheating and quenching → tempering and carbonitriding → cooling to a temperature of Ac 1 point or lower → reheating and quenching →
It shows the relationship between the amount of retained austenite when tempered and rolling fatigue life in an environment in which foreign matter is mixed.
【００３４】図５は、鋼Ｎｏ．１および鋼Ｎｏ．６〜１
５を浸炭・焼入れ（Ｃ．Ｐ．：１．２％）→焼もどしを
施した時の平均粒径０．５μｍ以下の炭化物または炭窒
化物についての面積率／平均粒径と異物が混入した環境
下での転動疲労寿命の関係を示したものである。FIG. 5 shows steel No. 1 and steel No. 1 6-1
No. 5 was carburized / quenched (CP: 1.2%) → tempered. Area ratio / average particle size of carbide or carbonitride having an average particle size of 0.5 μm or less and foreign matter were mixed. It shows the relationship between rolling fatigue life under environment.
【００３５】図１〜４の結果から以下のことが分かる。
即ち、表３および図１，２より高炭素クロム軸受鋼に浸
炭または浸炭窒化した後、焼入れ・焼きもどしを施した
後の軸受部材の最表層部において、残留オーステナイト
量を１０〜５０ｖｏｌ％、平均粒径０．５μｍ以下の炭
化物または炭窒化物の面積率／平均粒径を４％／μｍ以
上の範囲に制御することにより、異物が混入した環境下
での転動疲労寿命が向上し、従来のころがり軸受部材に
比べて優れた転動疲労寿命が得られる。The following can be seen from the results shown in FIGS.
That is, from Table 3 and FIGS. 1 and 2, after the carburizing or carbonitriding of the high carbon chrome bearing steel, and the quenching and tempering treatment, the residual surface austenite content in the outermost surface layer portion of the bearing member is 10 to 50 vol%, average By controlling the area ratio / average particle size of carbides or carbonitrides with a particle size of 0.5 μm or less within the range of 4% / μm or more, rolling fatigue life in an environment in which foreign matter is mixed is improved, Excellent rolling contact fatigue life can be obtained compared to rolling bearing members.
【００３６】また、表４および図３，４より高炭素クロ
ム軸受鋼を浸炭または浸炭窒化を施した後、Ａｃ1 点以
下の温度まで冷却して再度加熱して焼入れ・焼きもどし
を施した場合には、浸炭または浸炭窒化後、再加熱せず
に焼入れ・焼きもどしを施した場合に比べ、平均粒径
０．５μｍ以下の微細な炭化物あるいは炭窒化物の析出
量が増加し、さらに転動疲労寿命が向上していることが
わかる。Further, from Table 4 and FIGS. 3 and 4, after carburizing or carbonitriding high carbon chromium bearing steel, cooling to a temperature of Ac 1 point or lower and heating again to quench and temper. In comparison with the case of quenching and tempering without reheating after carburizing or carbonitriding, the precipitation amount of fine carbides or carbonitrides with an average particle size of 0.5 μm or less increases, and rolling It can be seen that the fatigue life is improved.
【００３７】尚、本発明における浸炭または浸炭窒化処
理時間は２〜３時間であり、従来技術の低合金鋼を浸炭
または浸炭窒化処理するのに必要な４〜１０時間に対し
て処理時間の短縮を図ることができた。The carburizing or carbonitriding treatment time in the present invention is 2 to 3 hours, which is shorter than the 4 to 10 hours required for carburizing or carbonitriding the conventional low alloy steel. Could be achieved.
【００３８】さらに、表５および図５より、高炭素クロ
ム軸受鋼にＣｒ，Ｍｏ，Ｖ，Ｎｂ，Ｗを添加あるいは増
量添加した場合、いずれの場合も異物が混入した環境下
での転動疲労寿命がより向上していることは明らかであ
る。Further, from Table 5 and FIG. 5, when Cr, Mo, V, Nb, and W are added or increased to the high carbon chromium bearing steel, rolling fatigue in an environment in which foreign matter is mixed is observed in any case. It is clear that the life is improved.
【００３９】[0039]
【発明の効果】本発明は以上の様に構成されているの
で、異物が混入した環境下での転動疲労寿命が飛躍的に
向上し、従来のころがり軸受部材に比べて優れた転動疲
労寿命を有し、かつ、低合金鋼を浸炭または浸炭窒化処
理するのに比べて処理時間の短縮を図ることのできるこ
ろがり軸受部材を提供できることとなった。EFFECTS OF THE INVENTION Since the present invention is constructed as described above, the rolling contact fatigue life in an environment in which foreign matter is mixed is drastically improved, and rolling contact fatigue superior to that of conventional rolling bearing members is achieved. It has become possible to provide a rolling bearing member that has a long life and can shorten the treatment time as compared with carburizing or carbonitriding a low alloy steel.
【図１】面積率／平均粒径と転動疲労寿命の関係を示す
グラフである。FIG. 1 is a graph showing the relationship between area ratio / average grain size and rolling contact fatigue life.
【図２】残留オーステナイトと転動疲労寿命の関係を示
すグラフである。FIG. 2 is a graph showing the relationship between retained austenite and rolling contact fatigue life.
【図３】面積率／平均粒径と転動疲労寿命の関係を示す
グラフである。FIG. 3 is a graph showing the relationship between area ratio / average particle diameter and rolling contact fatigue life.
【図４】残留オーステナイトと転動疲労寿命の関係を示
すグラフである。FIG. 4 is a graph showing the relationship between retained austenite and rolling contact fatigue life.
【図５】面積率／平均粒径と転動疲労寿命の関係を示す
グラフである。FIG. 5 is a graph showing the relationship between area ratio / average grain size and rolling contact fatigue life.
Claims (2)
転動体の少なくとも１つは、高炭素クロム軸受鋼を浸炭
または浸炭窒化した後、焼入れ・焼もどしを施したもの
であり、該軌道輪及び／又は転動体の最表層における残
留オーステナイト量が１０〜５０ｖｏｌ％、上記軌道輪
及び／又は転動体の最表層に含有される平均粒径０．５
μｍ以下の炭化物または炭窒化物の面積率／平均粒径が
４％／μｍ以上の範囲にあることを特徴とするころがり
軸受部材。1. At least one of a race ring and a rolling element in a rolling bearing member is obtained by carburizing or carbonitriding high carbon chrome bearing steel, and then quenching and tempering the race. The amount of retained austenite in the outermost layer of the rolling element is 10 to 50% by volume, and the average particle diameter contained in the outermost layer of the bearing ring and / or the rolling element is 0.5.
A rolling bearing member characterized in that the area ratio / average particle diameter of carbides or carbonitrides of μm or less is in the range of 4% / μm or more.
しの間で、Ａｃ1 点以下の温度まで冷却後再度加熱した
ものである請求項１に記載のころがり軸受部材。2. The rolling bearing member according to claim 1, wherein the rolling bearing member is reheated after being cooled to a temperature of Ac 1 point or less between carburizing or carbonitriding and quenching / tempering.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22827795A JPH0972342A (en) | 1995-09-05 | 1995-09-05 | Rolling bearing member |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22827795A JPH0972342A (en) | 1995-09-05 | 1995-09-05 | Rolling bearing member |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0972342A true JPH0972342A (en) | 1997-03-18 |
Family
ID=16873965
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22827795A Withdrawn JPH0972342A (en) | 1995-09-05 | 1995-09-05 | Rolling bearing member |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0972342A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000212721A (en) * | 1998-11-19 | 2000-08-02 | Nsk Ltd | Rolling member excellent in wear resistance |
| JP2001323939A (en) * | 2000-05-18 | 2001-11-22 | Nsk Ltd | Rolling bearing |
| JP2003065226A (en) * | 2001-08-30 | 2003-03-05 | Ntn Corp | Thrust needle bearing for swash plate type compressor |
| WO2006068205A1 (en) * | 2004-12-24 | 2006-06-29 | Jtekt Corporation | Rolling-sliding elements and process for production of the same |
-
1995
- 1995-09-05 JP JP22827795A patent/JPH0972342A/en not_active Withdrawn
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000212721A (en) * | 1998-11-19 | 2000-08-02 | Nsk Ltd | Rolling member excellent in wear resistance |
| JP2001323939A (en) * | 2000-05-18 | 2001-11-22 | Nsk Ltd | Rolling bearing |
| JP2003065226A (en) * | 2001-08-30 | 2003-03-05 | Ntn Corp | Thrust needle bearing for swash plate type compressor |
| WO2006068205A1 (en) * | 2004-12-24 | 2006-06-29 | Jtekt Corporation | Rolling-sliding elements and process for production of the same |
| JPWO2006068205A1 (en) * | 2004-12-24 | 2008-06-12 | 株式会社ジェイテクト | Rolling and sliding parts and manufacturing method thereof |
| JP5094126B2 (en) * | 2004-12-24 | 2012-12-12 | 株式会社ジェイテクト | Rolling and sliding parts and manufacturing method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4022607B2 (en) | Manufacturing method of high surface pressure resistant member | |
| JP5094126B2 (en) | Rolling and sliding parts and manufacturing method thereof | |
| CN101115859B (en) | High-concentration carburized/low-strain quenched member and process for producing the same | |
| JPH0578814A (en) | Rolling bearing | |
| JPH06341441A (en) | Rolling bearing | |
| JP4047499B2 (en) | Carbonitriding parts with excellent pitting resistance | |
| JP2006200003A (en) | Heat-treated article and heat treatment method | |
| JP2010255095A (en) | Method for manufacturing bearing-component excellent in rolling fatigue characteristics under foreign matter environment | |
| JPH0525609A (en) | Rolling bearing | |
| JP2006200627A (en) | Rolling bearing component and its manufacturing method, and rolling bearing | |
| JP2003226918A (en) | Bearing part, heat treatment method therefor and roll bearing | |
| JP2004076125A (en) | Rolling member | |
| JP4923776B2 (en) | Rolling and sliding parts and manufacturing method thereof | |
| JPH06293939A (en) | Bearing parts excellent in high temperature rolling fatigue characteristic | |
| JP2002060847A (en) | Heat resistant carburized rolling bearing parts and method for producing the same | |
| JP2019218582A (en) | Mechanical component | |
| JP6055397B2 (en) | Bearing parts having excellent wear resistance and manufacturing method thereof | |
| JP6939670B2 (en) | Steel parts with excellent rolling fatigue characteristics | |
| JP2002180203A (en) | Needle bearing components, and method for producing the components | |
| JP3006034B2 (en) | High strength mechanical structural members with excellent surface pressure strength | |
| JP2000129347A (en) | Production of high strength parts | |
| JP4569961B2 (en) | Manufacturing method of parts for ball screw or one-way clutch | |
| JP2007113027A (en) | Heat treatment method for steel, method for producing rolling-supporting apparatus and rolling-supporting apparatus | |
| JP2002069572A (en) | Soft-nitriding steel having excellent bending fatigue strength | |
| JP5402711B2 (en) | Steel product having carbonitriding layer and method for producing the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 20021105 |