Carbon C: 0.28 ~ 0.33 
 Silicon Si: 0.15 ~ 0.35 
 Mn Mn: 0.40 ~ 0.60 
 Sulfur S: allow the residual content of ≤ 0.040 
 Phosphorus P: Allow the residual content of ≤ 0.035 
 Chromium Cr: 0.80 ~ 1.10 
 Ni: to allow the residual content of ≤ 0.030 
 Cu: to allow the residual content of ≤ 0.030 
 Mo Mo: 0.15 to 0.25 [2]