Study of work function and dry sliding wear behavior of Fe-based hardfacing alloys with and without nano rare earth oxides

In this paper, work function and dry sliding wear behavior of the hardfacing alloys with different content of nano rare earth oxides (REOs) were studied. The microstructural changes of the hardfacing alloys with and without nano REOs were observed. The integral work function of hardfacing alloys was measured by Scanning Kelvin Probe. The individual work function of the constituent phases was indirectly measured and compared by Atomic Force Microscope. Pin-on-disc wear testing machine was used to conduct dry sliding wear tests. The results showed that nano REOs changed the volume fractions of primary carbide, eutectic carbide and the matrix. Nano REOs increased the integral work function of hardfacing alloys by increasing the volume fraction of primary carbide with high work function. The work functions of primary carbide and eutectic carbide were similar, which were higher than that of the matrix. Nano REOs improved the wear resistance of hardfacing alloys. The variation trends of friction coefficient and integral work function with the content of nano REOs were reversed. The variation trends of wear rate and integral work function with the content of nano REOs were also reversed. The hardfacing alloy having higher integral work function had better wear resistance.