45 Steel

Material designation: 45 
  Diagram No.: 273
  GB designation: 45
  Mat.No. (Wr.Nr.) designation: ~1.1191
  Chemical composition in weight %: 0.42-0.50% C, 0.17-0.37% Si, 0.50-0.80% Mn, max. 0.035% P,
  max. 0.035% S, 0.25% Cr, 0.30% Ni, 0.25% Cu
  Steel group: Structural and constructional steels
  Applications: No data
  Comment: Quality carbon steels