GCr15 is a common steel which is used to produce balls and rings of bearing. The product has characteristics of the uniform-chemical composition, low percentage of harmful elements, high purity, well-distributed carbide, good surface quality. It also has characteristics of a wide scope of plastic，stable heat-treatment quality, uniform, and high hardness, high wear resistance，high strength of touching fatigue. It has excellent machining property after spheroidize annealing. GB GCr15 bearing steel is GB standard Alloy Bearing steel, It belong to the high-quality high carbon, alloy chromium, manganese steel. GB GCr15 properties is a chromium, manganese alloy steel specification. GCr15 is equivalent to AISI 52100, DIN 100Cr6. Most applications can replace each other.