About bearing stiffness, bearing inner and outer rings and rolling elements made of high chrome steel GCr15 bearing steel or GCr15SiMn two kinds.

Finished bearing rings Rockwell hardness of HRC60-65; products bearing rolling elements in Rockwell hardness HRC60-66. Wherein, GCr15 bearing steel ball Rockwell hardness within a range of HRC62-66; GCr15SiMn roller bearing steel hardness in Rockwell HRC60-64, Rockwell HRC60-66 ball within range.

So hardness HRC is what does that mean? For example: the hardness of the blade family with a kitchen knife is generally about HRC50, surgical tools and military tool steel to be polished some are within Rockwell hardness HRC60. Metal turning machines with alloy heads also in the conventional hardness Rockwell HRC62 ~ 65 or so. Rolling relative hardness is relatively hard, deep processing of products bearing want must be processed with special equipment and tools.