Influence of oxide reinforcement materials on high-temperature oxidation resistance of Ni3A1 matrix composites.

摘要

The oxidation resistance of Ni(sub 3)Al-based metal matrix composites was studied in high-temperature air under isothermal and thermal cycling conditions as a function of the composition and form of oxide reinforcement material. The incorporation of oxide fibers Al(sub 2)O(sub 3), HfO(sub 2), or Al(sub 2)O(sub 3)--ZrO(sub 2) or particles into the Ni(sub 3)Al matrix led to oxidation rates significantly greater than that for the monolithic aluminide. The increase in susceptibility was primarily due to internal oxidation along the fiber- (or particle-) matrix interfaces and depended on the type of reinforcement material and its deposition in the matrix. The results suggest that the choice of reinforcement material and the method of materials processing will be important considerations in the design of oxidation-resistant Ni(sub 3)Al composites. 10 refs, 4 figs.