Effect of tempering temperatures on microstructure and mechanical properties of high-strength steel

Abstract

Abstract This study thoroughly examines the effects of tempering temperature on the structure and mechanical properties of high-strength steel. The objective is to establish a solid foundation of raw materials for the production of relevant equipment. Experimental results show that: when tempering temperatures between 180°C~300°C, with the increase of tempering temperature, the tensile stress of the material decreases gradually, and the yield strength tends to increase. The comprehensive mechanical properties of the alloy are optimized in plasticity and toughness, and it can be seen that the strength reaches an excellent balance at 180°C. The carbide precipitation and impact fracture characteristics are analyzed by scanning electron microscopy and transmission electron microscopy, and it is found that a large number of needle-shaped ε-carbides are precipitated in the martensite lath, and the size of the ε-carbides increases with the increase in tempering temperature, which is the reason for the gradual decrease in the yield strength of the experimental steel with the increase in tempering temperature.