论文部分内容阅读
以 Ti, Al, TiO2和 Nb2O5混合粉为原料,采用热压反应合成技术制备了 Al2O3/TiAl 复合材料。对复合材料的微观组织与力学性能进行了研究。结果表明:产物由γ-TiAl, α2-Ti3Al, Al2O3和 NbAl3相组成。原位反应形成的细小 Al2O3粒子主要分布在基体晶界处。随着 Nb2O5含量的增加,晶粒明显细化,Al2O3粒子呈弥散分布在基体中。最终形成了由γ和γ+α2构成的特殊组织。随着 Nb2O5含量的增大,复合材料的硬度逐渐增大,抗弯强度和断裂韧性在 Nb2O5含量为 6 wt%时达到最大,分别为 398.5 MPa 和 6.99 MPa·m1/2。
The Al2O3 / TiAl composites were prepared by hot press reaction synthesis using Ti, Al, TiO2 and Nb2O5 as raw materials. The microstructure and mechanical properties of the composites were studied. The results show that the product consists of γ-TiAl, α2-Ti3Al, Al2O3 and NbAl3 phases. In situ reaction of the formation of small Al2O3 particles are mainly distributed in the matrix grain boundaries. With the increase of Nb2O5 content, the grain size is obviously refined, Al2O3 particles are dispersed in the matrix. Eventually formed by the γ and γ + α2 constitute a special organization. With the increase of Nb2O5 content, the hardness of composites gradually increases, and the flexural strength and fracture toughness reach the maximum at Nb2O5 content of 6 wt%, which are 398.5 MPa and 6.99 MPa · m1 / 2, respectively.