Description:

40Cr is under the standard of GB/T 3077-1999 inChina,40Cr steel is one of the most widely used steel in machinery manufacturingfield. After quenching and tempering, 40Cr has good comprehensive mechanicalproperties, good low temperature impact toughness and low notch sensitivity. itshardenability is good , when water quench hardening can reach to Ф 28 ~ 60 mm,when oil quenching hardening can reach to Ф 15 ~ 40 mm. In addition, except quenchingand tempering, it also fits for cyanide and high frequency quenching process. Hasgood machinability, when hardness is HB174 ~ 229, the relative cuttingmachining is 60%. The steel is suitable for manufacturing to medium-sizedplastic mold.

Equivalent grades:

JIS SCr440

DIN 1.7045

DIN 41Cr4/42G4

BS 41Cr4

SS 2245

ASTM 5140

ISO 41Cr4

Heat treatment:

AC3= 780 C

Normalizing: 850 C, oil cooling, hardness 179~229HBS

Softening treatment: 740~760 C, holding 4~6 hours, slow cool at 5~10℃/h,cool to under 600 C,

Air cooling.