在ZTM15(2Y)中加入Al2O3粒子，可以改善材料的微观结构，使ZTM15(2Y)材料的室温力学性能提高。尤其是材料的断裂韧性，由4.0MPa*m1/2增至7.8MPa*m1/2，其主要贡献源于微裂纹增韧。但由于Al2O3粒子的引入，增加了ZTM15(2Y)基体中微裂纹的密度，所以不能有效抑制ZTM15(2Y)材料低温时效处理力学性能下降现象，相反，将加速材料力学性能的退化。%A microstructure with a narrow ZrO2 grain size distribution in the fine mullite grain matrix was obtained by the addition of 5vol%～10vol%Al2O3 particles.The effect of Al2O3 particles on the low tempe-rature ageing of ZTM15(2Y)/Al2O3 composites was studied. The result shows that compared with ZTM15(2Y), the room temperature mechanical properties of ZTM15(2Y)/Al2O3 composites, especially the toughness, are remarkably improved, and toughness could reach 7.8MPa*m1/2. The microcraking is the dominant toughening mechanism. The addition of Al2O3 particles could not inhibit the degradation behavior of ZTM15(2Y) because of the increase of microcraks, on the contrary, enhanced t-m transformation during ageing.
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