Effects of quenching temperature and tempering temperature on 42 CrMo cold working die steel were investigated by tensile testing

impacting testing

hardness measurement and microstructure observation.The results show that

with tempering at 200 ℃

with the increase of quenching temperature

the tensile strength is increased firstly and then decreased

while

elongation

section shrinkage and impact power are decreased.With tempering at 600 ℃

with the increase of quenching temperature

the tensile strength of die steel is reduced lightly ahead of 1 040℃

while the elongation

section shrinkage

impact and hardness are decreased.After 200 ℃tempering

the strength of the steel mold meet the requirements

however

the elongation and impact power energy are lower than the standard requirements.After tempering at 600 ℃

the strength

plasticity and toughness meet the requirements of cold work die steel substrate.