20CrMnMo, is a Chinese national standard alloy steel grades. Unified digital code: A34202.

Chemical composition
Mass fraction (%):

Carbon C: 0.17 ~ 0.23

Si Si: 1.17 ~ 1.37

Manganese Mn: 0.90 ~ 1.20

     Sulfur S: to allow the residual content of ≤ 0.035

     Phosphorus P: allow the residual content ≤ 0.035

Chromium Cr: 1.10 ~ 1.40

Ni: to allow the residual content of ≤ 0.030

Copper Cu: to allow the residual content ≤ 0.030

Mo Mo: 0.20 ~ 0.30