Abstract: To solve the problem of insufficient plasticity and toughness in low alloy wear-resistant steel, the quenching-tempering(Q-T) process of the ZG30CrMnSiMoVTi steel was optimized and improved by means of JmatPro and ANSYS softwares. The microstructure and comprehensive properties of the tested steel under two heat treatment processes were studied by using metallographic observation, hardness, impact and tensile tests. The results show that the water-air alternating cycle controlled cooling+tempering process with water quenching time of 10 s, air quenching time of 8 s, and cycling for 3 times can be used as the optimized heat treatment process obtained from the simulation and analysis of the steel piece of 60 mm×250 mm. For the average hardness from heart to surface, there is not much difference between 49.75 HRC after Q-T treatment and 46 HRC after 3 cycles, but the hardness at different positions after 3 cycles and tempering is more uniform. Compared with the specimen treated with Q-T, the tensile strength of the specimen after 3 cycles and tempering increases from 1246.3 MPa to 1551.7 MPa, the yield strength increases from 1038.6 MPa to 1293.1 MPa, the elongation after fracture increases from 10.5% to 12.6%, and the impact absorbed energy increases from 17.7 J to 29.1 J. Compared with the Q-T treated one, the specimen with water quenching time of 10 s, air quenching time of 8 s, and three cycles + tempering has a more uniform microstructure, and its hardness distribution is more uniform, the tensile strength, yield strength and impact absorbed energy are all improved to a certain extent.

Key words: JmatPro software, ANSYS software, low alloy wear-resistant steel, Q-T heat treatment, water air alternating circulation control cooling+tempering process