steel balls manufacturing
microstructure is martensitic steel, high production process requirements, less domestic enterprises can produce stainless steel 440C, 440C are able to produce materials companies often dubbed special stainless steel in the world. Heat treatment process more complicated, easy to crack, and high precision, is a ball the hardest steel ball: HRC -58. Hardness approaching ball bearings, but the former has a stronger anti-rust, corrosion resistance.