Specifications

Bearing steel bar commonly used for the production of bearing steel tube,tapered roller, roller bearing ect.

GCr15 bearing steel is a kind of high carbon chromium bearing steel alloy content is less, have good performance, the most widely used. After quenching and tempering has high and uniform hardness, good abrasion resistance, high contact fatigue performance. The cold steel processing plastic medium, cutting performance in general, poor welding performance, on the formation of white spots sensitive performance, have the temper brittleness.

1 common annealing: 790-810 degree heating, furnace cooling to 650 degrees, air cooling -- HB170-207

2 isothermal annealing: 790-810 degrees 710-720 degrees temperature, heating, air cooling -- HB207-229

3 fire: 900-920 degree heating, air cooling -- HB270-390

4 high temperature tempering: 650-700 degree heating, air cooling -- HB229-285

5: 860 degree heating quenching, oil quenching -- HRC62-66

6: 150-170 degrees low temperature tempering tempering, cooling -- HRC61-66

7 carbonitriding carbonitriding: 820-830 degrees 1.5-3 hours, oil quenching, -60 degrees to -70 degrees cryogenic treatment

+150 to +160 tempering, cooling -- HRC ≈ 67

The smelting quality of bearing steel demand is very high, need the content and distribution of strict control of sulfur, phosphorus and non metallic inclusions, because of the great life of nonmetallic inclusion content and distribution on the influence of bearing steel. The basic quality of bearing steel demand is pure and homogeneous microstructure. Pure is less impurities and non-metallic inclusion, microstructure is to fine carbides in steel, should be uniform distribution. Inclusion content is higher, the shorter the life. In order to improve the quality of smelting, has recently adopted by electric furnace and electroslag remelting, also by vacuum melting, vacuum consumable refining and other new technology to improve the quality of bearing steel.