Elucidating the room- and high-temperature sliding wear mechanisms of high-strength low-alloy steel exhibiting excellent tribological performance

High-strength low-alloy (HSLA) steel typically fails during service because of high-temperature wear. The tribological performance of HSLA steel prepared by powder metallurgy or vacuum arc melting was studied at 20 °C and 200 °C, and the microstructural evolution and wear mechanism were elucidated. The results revealed that as the temperature increased from 20 °C to 200 °C, the average friction coefficient and wear rate of the two types of samples decreased. Compared with the vacuum arc melting samples, the powder metallurgy samples have excellent frictional properties, with a wear rate of 1.31 × 10⁻⁷ g/(N·m) at 200 °C, corresponding to only 47.12% of that of the vacuum arc melting samples. The adhesion layer composed of Fe₂O₃ and Fe₃O₄ has excellent lubrication effects. The formation of high-density dislocations, high surface hardness, and significant refinement of the surface microstructure improve the ability to resist plastic deformation, thereby preventing the formation of large-scale cracks that cause extensive peeling.