FABRICATION OF Al₂O₃/HEAT-RESISTANT STEEL COMPOSITE AND ITS WEAR-RESISTANCE AT HIGH TEMPERATURE AND ABRASIVE

Because of the special properties of Al₂O₃ and heat-resistant steel at high temperature, the composite of Al₂O₃ particle reinforced heat-resistant matrix would possess good wear-resistance at the situation of high temperature and abrasive. After getting the coating on 154~200 μm Al₂O₃ particles by CVD method, the composites are made by the vacuum infiltration process, the particle volume fractions are changed from 18% to 52% through adding the heat-resistant steel particles into Al₂O₃ particles, and then the wear-resistances of the composites at high temperature have been investigated. The results show that the wear-resistant properties of all composites are better than those of heat-resistant steel, and the best composite is the one in which the coated-Ni Al₂O₃ particle volume fraction is 39%, whose wear resistance is 3.27 times that of heat-resistant steel at the situation of 900℃ and abrasive wear. Then the wear mechanism of particle composites and the effects of particle volume fraction on wear are analyzed by SEM.