Original Article Effect of MoS2 on the tribological properties of in situ Fe3Al-20wt%

Fe3Al-20wt % Al2O3-4wt % Cr composites containing 0, 5 and 8wt % MoS2 were subjected to mechanical alloying-inducing self-propagating high temperature synthesis with subsequent hot-pressing sintering. Microstructures of the composites were studied by X-ray diffraction, scanning electron microscopy and energy dispersive spectrum analysis. Then the relative density, room temperature hardness and dry sliding wear behavior of the sintered composites at 25 C, 500 C and 800 C were tested and analyzed. The results showed that composites with different amounts of added MoS2 had good microstructure with high relative density and high hardness. The MoS2 decomposes during sintering with the formation of Fe3Mo3C and Cr2S3. Cr2S3 formed from the decomposition process may form a lubricating film that can decrease the friction coefficient. At 800 C, Fe3Al-20wt % Al2O3-4wt % Cr with 8wt % added MoS2 exhibited a friction coefficient that was nearly 50 % lower than that for the sample with no MoS2 addition. Addition of 8wt % MoS2 trans-formed the wear mechanism from adhesive wear to microploughing