... and painting. We can produce discs made of qualified spring steel 65Mn or boron steel from ... discs according to customers’ drawings and samples. Common Specifications of DiscDia.Concavity ThicknessMMINCHMMMM255101233051219333013253355143834101538~50343017573,44601838~603,448019573, ... 2008,10,1296038120-2008,10,12 chemical composition of our 65Mn steelcompositionCMnSiSPNiCrCuNbcontents %0.62~0.700. ...