1. black or machined surface 2. ESR 3. forged ( dimension as per customers requirement) 4. annealed <=HB229 1. ApplicationFull hardness(HRC52-54)plastic moulds with high polishing and long service life requirements, such as Bakelite plastic moulds, Tin,lead,Zn and Al alloy die casting mould(such as engine radiator, lights and other decoration products), Aluminum extruded moulds(such as Aluminum ...