Thermal simulation study on vacuum laser welding process of 42CrMo steel

Abstract To reduce the quenching sensitivity of welded structures such as gears and transmission shafts, this paper employs vacuum laser welding and establishes a temperature field simulation model, as well as a combined model of Gaussian surface heat source and Gaussian volume heat source. The thermal cycle patterns of the laser welding process of 42CrMo steel under different vacuum pressures are analyzed. The results show that the simulated weld seam model and temperature field distribution are consistent with the actual weld height. The cooling rate at the lower part of the weld seam is significantly higher than that at the upper part. As the vacuum pressure increases, the cooling rate gradually decreases.