42CrMo Steel Material is high strength steel. It has great toughness, strength and hardenability. After quenching and tempering treatment, it will get better fatigue limit and shock resistance ability. It usually is used without obvious temper embrittlement after the quenching and tempering treatment. And its low-temperature impact toughness is good. So 42CrMo steel material round bar or sheet was widely used in the big or medium type plastic mold with certain strength and toughness. The properties of 42CrMo are close to the 35CrMo. But the content of carbon and chromium are higher than 35CrMo, so the strength and hardenability are better than 35CrMo material.
What is 42CrMo steel material used for?
Compare with the 35CrMo, 42CrMo is a better option. Due to its great properties, people usually use 42CrMo steel round bar or plate to make the important fittings those with higher strength and bigger cross-section size than 35CrMo. Such as the shaft, gear, connection rod, spring, engine cylinder, 1200-2000mm petroleum drill attaches, and etc.
42CrMo Steel Material Chemical Composition
42CrMo Mechanical Properties
- Tensile Strength: no less than 1080 MPa
- Yield Strength: no less than 930 MPa
- Elongation: no less than 12%
- Rate of Reduction of Area: 45%
- Impact Absorbing Energy: no less than 63 J
42CrMo Steel Heat Treatment
Annealing in 760±10℃, furnace cooling to 400℃ then air cooling.
Normalizing in 760±10℃, air cooling after out of the furnace.
Notes About Quenching and Tempering Treatment
Must pay attention to the temperature of liquid coolant. And must make sure there are no oil contamination or other impurities. Otherwise, the hardness of steel will be not enough or out of the balance.
Quenching and tempering for billet steel material without processing, then it will get non-uniform hardness. So processing of forging or grinding is necessary before the Q+T.