High carbon chromium bearing steel



      What are the grades, uses and characteristics of high carbon chromium bearing steels? The bearing network will be introduced in detail for everyone.

       High carbon chromium bearing steels have high contact fatigue strength and wear resistance. Many grades are fully hardened steels such as GCr15 GCr15SiMn, GCr15SiMo, and GCr18Mo. However, since some bearings require good toughness in the core and high hardness on the surface, a hardened bearing steel such as GCr4 has been developed.

       1 GCr15 (fully hardened steel) GCr15 is a typical steel grade of high carbon chromium bearing steel, which has high hardness, wear resistance and contact fatigue strength after quenching and tempering. Its hot workability and workability are good, the hardenability is moderate, but the weldability is poor. GCr15 has a large white point sensitivity, but this defect can be eliminated in bearings that are vacuum degassed. It is used to manufacture rolling bearing rings with wall thickness ≤12mm and diameter ≤250mm, or to manufacture cones, cylinders, spherical rollers and all sizes of needles with diameter ≤22mm. It can also be used to make molds, gauges and woodworking tools as well as mechanical parts with high elastic limit and high fatigue strength.

       2 GCr15SiMn (highly hardened steel) improves the content of silicon and manganese on the basis of GCr15 steel, so the hardenability, elastic limit and wear resistance are better than GCr15. The rolling bearing parts produced therefrom should not be used above 180 °C. It is used for the manufacture of rolling bearing rings with wall thickness >12mm, outer diameter >120mm, steel balls with diameter >50mm and cones, cylinders, spherical rollers and all sizes of needles with diameter >22mm. Other uses are the same as GCr15.

       3 GCr15SiMo (highly hardened steel) increases the silicon content based on GCr15 and adds molybdenum. It has high hardenability, good wear resistance, high fatigue strength and good overall performance. It is suitable for the manufacture of rolling bearing rings and steel balls, rollers and the like in a large size range.

       4 GCr18Mo (high-hardenable steel) adds molybdenum with a mass fraction of 0.15%~0.25% on the basis of GCr15, and increases the content of each, so the hardenability and wear resistance are improved. The lower bainite austempering can be performed to achieve hardness and wear resistance similar to martensite quenching, and the impact, fracture toughness and flexural strength of the steel are improved, thereby improving the overall mechanical properties and life of the steel. A rolling bearing ring with a wall thickness of up to 20 mm can be produced, and the size range of the rolling bearing member is also expanded.

       5 GCr4 (restricted hardened steel) GCr4 is a low-hardenability rolling bearing steel. It has the properties of GCr15 fully hardened bearing steel and low carbon alloy carburized steel after being heated by volumetric tip and surface quenched and tempered. After quenching, the surface hardness is high, the surface resistance is good, the fatigue resistance is good, the core hardness is only 35~40HRC, and the toughness is good and impact resistant. It is mainly used to manufacture rolling bearing rings and rollers of various sizes and loads.https://www.supplyforever.com/