(1. 宝钛集团有限公司,宝鸡 721014;2. 陕西科技大学 材料科学与工程学院,西安 710021)
摘 要: 以Ti、Al、TiO2和Eu2O3为起始原料,原位热压合成Eu2O3掺杂Al2O3/TiAl复合材料。通过DSC、XRD及SEM分析,研究Eu引入对合成Al2O3/TiAl复合材料的微观结构和力学性能的影响。结果表明:体系在较低温度下烧结,其反应温度在900 ℃前后,复合材料主要由γ-TiAl、α2-Ti3Al、Al2O3和EuAlO3组成;含Eu相和Al2O3颗粒主要分布在基体相晶界处,Eu2O3的引入使基体及增强颗粒的晶粒细化,晶粒分布更均匀;当Eu2O3添加量为0.01 mol时,复合材料的弯曲强度和断裂韧性最大,其值分别为439 MPa和9.13 MPa·m1/2。
关键字: TiAl合金;Eu2O3掺杂;复合材料;显微组织;力学性能
(1. Bao Ti Group Co., Ltd., Baoji 721014, China;
2. School of Materials Science and Engineering, Shaanxi University of Science & Technology,
Xi’an 710021, China)
Abstract:Al2O3/TiAl composites were synthesized from the powder mixture of Ti, Al, TiO2, and Eu2O3, using the hot pressing reaction synthesis technique. The effect of the Eu2O3 doping on microstructures and mechanical properties of the Al2O3/TiAl composites was analyzed by thermal analysis (DSC), X-ray diffractometry (XRD), scanning electron microscopy (SEM). The results show that the reaction temperature of start materials is about 900 ℃. The phases of composites consist of γ-TiAl, α2-Ti3Al, Al2O3 and EuAlO3. The Eu containing phases and Al2O3 particles distribute at grain boundary of the matrix. The grains of the composites are remarkably refined and the distribution of Al2O3 particles are more uniform and dispersed;When the Eu2O3 content is 0.01 mol, the flexural strength and fracture toughness reach the maximum values of 439 MPa and 9.13 MPa·m1/2, respectively.
Key words: TiAl alloy; Eu2O3 doping; composites; microstructure; mechanical properties