Q460 steel with varying Ni contents was produced via the hot continuous rolling process. The microstructure and properties were examined using scanning electron microscopy (SEM) and universal testing machines. The results show that with increasing Ni content, the number of inclusions rises, and the microstructure gradually evolves from ferrite and pearlite to a mixture of ferrite, pearlite, and bainite. Due to the formation of bainite and refined grains, both the yield strength and tensile strength are significantly improved. However, with the increase in inclusions, the elongation and impact energy of the material do not exhibit substantial enhancement. Considering both cost and performance, the Ni content in Q460 steel is preferably controlled at 0.3%.
Qian et al. (Thu,) studied this question.