Steel name: AISI 4340
  Diagram No.: 343
  Type of diagram: CCT
  AISI designation: 4340
  UNS designation: G43400
  Chemical composition in weight %: 0.41% C, 0.87% Mn, 0.28% Si, 1.83% Ni, 0.72% Cr,
  0.20% Mo.
  Note: Carbon steel.
  Source: Bethlem Steel Company, USA.

  
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