Laser Glazing of 1080 Steel Surface for Improved Tribological Properties

Laser glazing of steel is being investigated as a means of improving its tribological properties for railroad and other applications. The microstructure of the surface layer on 1080 steel formed by the process was characterized by optical and transmission electron microscopy (TEM) and microhardness measurements. The microhardness increases were consistent with self-quenching of the 1080 steel, followed by tempering of adjacent areas. TEM revealed a very fine (5-10 nm) grain size. Friction and wear tests were conducted on glazed and unglazed materials with a pin-on-disc test rig. Laser glazing reduced both friction and wear during dry tests. The improved friction and wear performance is attributed to the microstructural changes of the near-surface region by laser glazing.