Rolling sliding member, method of manufacturing the same, and rolling bearing

Abstract

A steel material which contains 0.16 to 0.19% of carbon by mass, 0.15 to 0.35% of silicon by mass, 0.20 to 1.55% of manganese by mass, and 2.5 to 3.2% of chromium by mass, of which remaining part is formed of iron and incidental impurities, and which contains 0.01 to 0.2% of nickel by mass as an incidental impurity and higher than or equal to 0.001% and lower than 0.15% of molybdenum by mass as an incidental impurity, and which has a hardenability index of higher than or equal to 5.4 is subjected to a pre-processing step, a carbonitriding step, a process annealing step, a quenching step, a tempering step and a finishing step. Thus, there is obtained a rolling sliding member which contains 0.8 to 1.2% of carbon by mass and 0.05 to 0.4% of nitrogen by mass on the surface layer 0.05mm from the surface, is 700-840 in Vickers-hardness, 0.1mm deep from the surface, is 20 to 40% volume in residual gamma amount, and is 1.5 to 8% in carbide area rate, 0.03mm deep from the surface, is 300 to 500 in Vickers-hardness in axial length center and depth direction center of the rolling sliding surface, and is 50 to 100% in martensitic transformation rate.

Description

[0001] This application claims priority based on Japanese Patent Application No. 2012-222887 filed on October 5, 2012, including its specification, drawings, and abstract, and the entire contents thereof are cited herein. technical field [0002] The present invention relates to a rolling sliding part, a manufacturing method thereof, and a rolling bearing. Background technique [0003] Rolling and sliding parts used for large bearings such as industrial machines require materials with high hardenability in order to secure necessary strength. In addition, for rolling mill bearings in iron and steel equipment, for example, due to the harsh environment of use, in addition to improving the damage resistance against impact loads, etc., it is also required to improve the bearings that are prone to rust due to the immersion of rolling water, etc. Corrosion resistance in harsh environments, etc., and improve the rotational fatigue life of bearing components. In recent years, due to...

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Problems solved by technology

[0004] However, since the above-mentioned steel materials contain a large amount of rare metals such as nickel and molybdenum, they are expensive and have the disadvantage of increasing the manufacturing cost of rolling bearings.

On the other hand, it is considered to use steel materials that do not contain nickel and molybdenum, but in this case, the fracture resistance of bearing parts tends to decrease

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