Bearing steel is the most common material used in bearings, and there are two major types of bearing steel materials often used are: carburized bearing steel (G20Cr2Ni4A) and high-carbon chromium bearing steel (GCr15/GCr15SMn/GCr18M0). According to the specific understanding, share about these two bearing steel material performance comparison, hope that you can recognize when buying bearing materials, buy the most suitable bearing steel. Carburized bearing steel (G20Cr2Ni4A) G20Cr2Ni4A bearing steel is a high-quality alloy carburized steel (low carbon C: 0.17 ~ 0.23) used in the manufacture of bearing parts carburized steel, bearing parts made of this steel, after carburizing, quenching, tempering and other heat treatment processes, the surface has a very high hardness (hardness > HRC60) and a certain degree of wear resistance and high contact fatigue strength, low carbon C: 0.17 ~ 0.23 to ensure that the heart has good toughness (hardness > HRC33-48). This surface hardening heart has toughness characteristics, so that carburized bearing steel is particularly suitable for the impact load conditions can be stable work. In short, the advantages of carburized steel bearings are. 1, carburized quenched surface retains the state of compressive stress, good fatigue strength. 2, strong ability to withstand impact loads, the surface hardening layer with micro-cracking is not easy to expand internally. The surface has a high hardness while the heart hardness is low (generally 35HRC ~ 40HRC), compared with high-carbon chromium bearing steel, there is a better heart impact toughness. 3、The depth and concentration of carburization can be adjusted according to the need. 4、It is not limited by the size and wall thickness of bearing parts. High-carbon chromium bearing steel (GCr15/GCr15SMn/GCr18M0) High-carbon chromium bearing steel is a high-carbon alloy steel containing 1.30~1.65% chromium, which is characterized by relatively uniform and stable microstructure after heat treatment, high and uniform hardness, good wear resistance, high contact fatigue strength, good dimensional stability and corrosion resistance. After spheroidizing and annealing, its cutting and machining performance is good. This steel can meet the requirements for the use of bearings operating under general working conditions. 1, high carbon chromium bearing steel is widely used in the world, the most commonly used grades are GCr15 and GCr15SiMn, the amount in China accounts for about 80% of the total bearing steel, the performance of these two steels is basically the same, but GCr15SiMn steel hardenability than GCr15 steel, so for larger size bearing parts, it is appropriate to use GCr15SiMn steel. 2, GCr15 bearing steel is used to manufacture a large number of cars, tractors, tanks, aircraft, such as the use of engine bearings, machine tools, motors and other spindle bearings used in railroad vehicles, mining machinery, general machinery bearings. 3, GCr15SiMn bearing steel is mainly used to manufacture bearings with large wall thickness, such as a variety of large and extra-large bearings, mostly used in heavy machine tools and rolling mills without large impact loads under working conditions. 4, due to GCr15SiMn steel crack sensitivity, poor impact toughness, for the impact load of the thick-walled bearings can not fully meet the requirements of the use of the Ministry of Railways, the first proposed passenger car bearings are not allowed to use GCr15SiMn steel, there is a large wall thickness of the mill and mining bearings in the impact load bearing conditions, GCr15SiMn steel is also limited to use. Now GCr18Mo high hardenability steel has been developed, and wear resistance. Its performance is superior to GCr15SiMn steel, can be used in railroad bearings, rolling mill bearings, mining machinery bearings instead of GCr15SiMn steel.