Effect of Sub-temperature Quenching on Microstructure and Mechanical Properties of 25MnV Steel

The effect of sub-temperature quenching at different temperature on the tensile strength and hardness of 25MnV steel was investigated by orthogonal regressive principle.The microstructure of the steel after sub-temperature quenching was analyzed.The results indicate that the very fine lath martensite of 25MnV steel was obtained by sub-temperature quenching.The strip ferrite was distributed between martensite laths as the steel quenched at 830 ℃.In the temperature range of 810 to 830 ℃,the strength and hardness of the steel were increased along with the increasing of the quenching temperature.The best tensile strength and hardness could obtain in 25MnV steel when sub-temperature quenched at 830 ℃.