Effects of Austenization Temperature on Microstructure and Wear Properties of Low Alloy Wear-resistant Steel

The microstructure and precipitates of low alloy wear-resistant steel after quenching at different austenitizing temperatures and tempering were studied by SEM and TEM, and the wear mass loss was measured by abrasive wear tester.The results show that the microstructure of the test steel after austenizing at 860 ℃, 890 ℃, 920 ℃ then quenching and tempering at 200 ℃ is mainly lath martensite and a small amount of residual austenite. There are nanosize（Ti, Nb, V）C carbides and ε-Fe_xC particles in the matrix. The size of martensite lath are fine for the steel austenited at 860 ℃ because there are more insoluble carbides in the matrix, which prevents austenitic grain coarsizening. The hardness of the test steel decreases gradually and the abrasive wear resistant changes worse with the increase of austenite temperature. The wear mechanism is mainly plastic deformation and cutting. When the austenization temperature is 860 ℃, the wear resistant property of the test steel is best.