... ASTM, BS, DIN, GB, JIS used mattress spring tempered spring steel wire Grade:55CrSi,60Si2Mn,65Mn Dia:6.0~16.0mmStandards ... spring steel wire rod.2. Surface treatment: advanced technology of shot blasting, 100% rubbed smooth, almost can do zero defects for ... ’s requests to produce many kinds of strength level for spring steel wire. Mechanical property of steel wire in static level and Moderate ...