... :S20C,S25C,S35C,S45C,S55C,S60C;US Standard:AISI1020,AISI1040,AISI1045,AISI1050;Europe Standard:CK15,C.22,C45,CK45,C60,CK60 ... ,D/d,E/e;As forged condition straightness: ≤4mm/m, RT bar straightness: ≤2mm/mAs forged diameter tolerance: -0/+8mm; RT diameter tolerance:-0/+3 ... /C dateManufacturer:Jiangsu Zhuhong Forging Co.,Ltd Special carbon steel forged round bar C45/S45C/CK45