碳纤维增强Al 2 O 3 -20% Ni金属陶瓷复合材料的制备及组织性能
摘要
The CF/Al<inf>2</inf>O<inf>3</inf>-20% Ni metal-ceramic composites with 0%, 5%, 10% and 15% volume fraction of carbon fiber (CF) were prepared by sol-gel method and hot-pressing sintering. The phase composition, surface and fracture morphology were analyzed by XRD, SEM and EDS. The effect of CF content on CF/Al<inf>2</inf>O<inf>3</inf>-20%Ni hardness, bending strength, fracture toughness was studied. The fracture morphology of composites was analyzed by SEM and its mechanism was discussed. The results show that CF/Al<inf>2</inf>O<inf>3</inf>-20% Ni composites with well dispersed CF and evenly distributed Ni particles was obtained, and can prevent the loss CF in the sintering process at high temperature by the formation of &alpha;-Al<inf>2</inf>O<inf>3</inf> protective film layer on the CF surface. With the increase of volume fraction of CF, The hardness of the CF/Al<inf>2</inf>O<inf>3</inf>-20% Ni composites reduce, and its bending strength and fracture toughness first increase and then decrease. When the CF volume fraction is 10%, the bending strength and fracture toughness reach the maximum values, which increase by 79% and 134%, respectively, compared with the composites without CF. The addition of CF improves the strength and toughness of the CF/Al<inf>2</inf>O<inf>3</inf>-20%Ni composites. The toughening mechanism of CF/Al<inf>2</inf>O<inf>3</inf>-20%Ni is CF pull out, bridge and disbonding.<br/> &copy; 2017,Chinese Society for Composite Materials. All right reserved.