... +Q/T Ultrasonic Test:Sep1921 Class 3 C/c Hot forged steel round bar.Steel grade:Carbon steel:Chinese Standard ... 50#,60#;Japan Standard:S20C,S25C,S35C,S45C,S55C,S60C;US Standard:AISI1020,AISI1040,AISI1045,AISI1050;Europe Standard:CK15,C.22 ... ,20CrMo,38CrMoAl,40CrNiMo;48CrMo,5CrNiMo;Janpan Standard:SCM415,SCM420,SCM440,SNCM439,SNCM220; SACM645USA Standard:SAE4140,SAE4130,SAE9840,SAE4340,AISI4145H,SAE4150 ...