Mechanical Performance of Artificially Rusted Q500MC Structural Steel Subjected to High Temperature

Steel is prone to rusting in a corrosive environment, which results in a reduction of the effective bearing section of the steel structure. The stress concentration at the location of rusting causes brittle fracture of the steel structure during service. Although there is valuable research on the mechanism of corrosion and corrosion failure, research on the high-temperature mechanical properties of corroded steel is still limited. In this study, one-sided artificial accelerated corrosion of Q500 steel was performed, and a high-temperature steady-state tensile test was conducted on it. The degradation law and influencing factors of the high-temperature mechanical properties of corroded steel were discussed and analyzed using scanning electron microscopy (SEM) to quantify the corrosion surface morphology, and the volume corrosion ratio was used to characterize the degree of corrosion. The results showed that when the temperature was below 500°C, the attenuation of the ultimate load of corroded steel was influenced by the combined effect of temperature and corrosion. When the temperature exceeded 500°C, the influence of corrosion on the attenuation of the ultimate load tended to decrease due to the reduction in the material properties of steel. Furthermore, after the temperature exceeded 500°C, the elongation of the corroded section of the specimen increased gradually with the increase in temperature, and the elongation tended to be consistent even at different degrees of corrosion.