For studying the high-temperature wear behaviors of hardfacing metal layer of pile-up welding, a high-temperature wear tester was employed to evaluate the high-temperature wear resistance of the 414N hardfacing metal layer of 42CrMo continuous casting roller at 400, 500, 600 ℃, and SEM/EDX and XRD techniques were used to investigate the effect of wear temperature on the wear mechanism and properties of the hardfacing metal layer. Result showed that with the temperature increasing from 400 ℃ to 500 ℃, the wear resistance decreased greatly, and the average wear depths at 500 and 600 ℃ were 2.1 and 2.5 times of that at 400 ℃, respectively. The wear mechanism of 414N hardfacing metal layer was confirmed to be oxidative wear, abrasive wear and light oxide spalling wear at 400 ℃. In contrast, the wear mechanism at 500 and 600 ℃ was composed of oxidative wear and oxide spalling wear. During high-temperature wear, the oxide layer of hardfacing metal layer consisted of α’-Fe, cubic and hexagonal structural (Fe, Cr)2O3. When wear temperature was higher than 500 ℃, the white bright oxidization products in wear scar declined substantially, and the content of Cr in dark black oxide obviously decreased. Overall, the phase composition and Cr content of the oxide coating was the main factors to determine the high-temperature wear pathway and property of the hardfacing metal layer.
