Research on mechanical properties and constitutive model of LYP160 steel after high-temperature

The low yield point steel (LYP160) is a crucial energy-absorbing metallic material. However, concerns remain about changes in its mechanical properties after exposure to high temperatures. This study aims to deepen the understanding of the effects of high-temperature treatment and cooling processes on the mechanical properties of LYP160. Specimens of LYP160 were produced and subjected to reversed cyclic tests following high-temperature treatment and different cooling methods, including air cooling and water immersion cooling. The influence of temperature and cooling methods on hysteresis curves, energy absorption, and the mechanical properties of LYP160 were systematically examined. The corresponding failure mechanisms were analyzed using metallographic observation and fracture scanning. Based on the experimental results, a cyclic constitutive model for LYP160 post-high-temperature treatment was developed using the Chaboche cyclic model. These findings provide a scientific basis for engineering applications and design.