Abstract: Effect of different isothermal temperatures on the microstructure and wear resistance of a pearlitic wheel steel for high-speed railway was studied, and the microstructure and wear morphologies were observed by laser confocal microscope and scanning electron microscope. The results show that the pearlite microstructure is obtained by heat treatment within the pearlite transition temperature range. As the isothermal temperature increases, the interlamellar spacing of pearlite increases, the pearlite colony size decreases, and the microhardness of the tested steel decreases, while the wear loss of the pearlitic steel increases. And after grinding by sandpaper with large SiC particles, the wear loss of the pearlitic steel also increases. The worn surface of the pearlitic steel shows ploughing of varying depth with a series of spalling pits and tiny micro-cracks on it, and the ploughing depth increases with the increase of isothermal temperature. It is proved that the smaller the lamellar spacing of pearlite is, the better the wear resistance of the tested steel is.

Key words: pearlitic steel, isothermal temperature, abrasive wear, surface morphologies, wear resistance