Microstructure and wear characteristics of novel Fe-Ni matrix wear-resistant composites on the middle chute of the scraper conveyor

Fe-Ni matrix composites with varied amounts of graphite (Gr) were fabricated by spark plasma sintering system (SPS), and the microstructure and properties of composites were investigated in details. The results implied that Fe-Ni matrix composites were mainly composed of Fe, NiWCr, FeNi, FeCr, Fe3C, Fe3W3C, (Cr, Fe)(7)C-3, cored-eutectic structure (pearlite/Fe3C) and Gr. The variation of the average microhardness of Fe-Ni matrix composites depended on the content of Gr. It initially increased, followed by a decreasing trend with the increasing Gr content. When the Gr addition was 3 wt.%, the average microhardness reached a maximum value of about 355.3HV(0.5), which was about twice higher than that of 16Mn steel. Besides, the lowest wear rate of Fe-Ni matrix composites was also achieved with increasing Gr content to 3 wt.% under identical conditions due to the high hardness and the formation of a continuously low shear strength composite layer for the worn surface. (C) 2019 The Authors. Published by Elsevier B.V.