Abstract: Sixty LY160 steel specimens are designed and fabricated and subjected to uniaxial tensile tests after cooling from high temperature. First, the mechanical properties of LY160 steel subjected to temperatures ranging from 20 to 1 000 ℃ are obtained through heating, cooling, and tensile tests. Then, the mechanical properties of Q235, Q345, Q460, and Q690 steels after high-temperature heating and water cooling are compared. Finally, based on the experimental results, formulas describing the temperature-dependent mechanical parameters of LY160 steel after high-temperature heating and cooling are fitted. The results show that as the temperature increases, the color of the specimens darkens, and the luster gradually disappears. In addition, the yield plateau in the stress-strain curve gradually disappears with increasing temperature, while water cooling causes its premature disappearance in LY160 steel. Temperature and cooling methods have a significant impact on the yield strength and elongation of LY160 steel, while their influence on ultimate strength and elastic modulus is relatively small. Below 300 ℃, the mechanical properties remain similar to those at room temperature. Above 300 ℃, the trends in yield strength and ultimate strength are consistent, but the change in yield strength is greater. Significant changes in elongation only occur from 700 ℃ onwards, and the change in elastic modulus is not pronounced. The mechanical properties of different grades of steel after cooling from high temperature differ markedly, and LY160 steel exhibits notable changes in yield strength at relatively low temperatures (400 ℃). The experimental results match well with the fitting curves, and the fitting formulas allow for the rapid acquisition of the mechanical properties of LY160 steel after high-temperature exposure.

Key words: LY160 steel, mechanical property after high temperature, cooling mode, fitting formula