热压反应合成Al_2O_3-Ho_2O_3/TiAl复合材料  

Ho-doped Al_2O_3/TiAl composites fabricated by in-situ reaction synthesis

作　　者：王芬[1] 许红娅[1] 朱建锋[1] 王少龙[1] 解宇星 

机构地区：[1]陕西科技大学材料科学与工程学院,西安710021 [2]中国航天科技集团第六研究院,西安710077

出　　处：《粉末冶金技术》2010年第1期34-38,共5页Powder Metallurgy Technology

基　　金：国家自然科学基金资助项目(50672056);陕西科技大学研究生创新基金资助项目

摘　　要：利用Al-Ti-TiO2-Ho2O3体系原位反应合成了Ho掺杂Al2O3/TiAl复合材料。采用DTA结合XRD分析对体系反应过程进行了探讨。借助XRD、EDS和SEM等手段,对放热体系的物相组成及晶粒微观形貌进行了分析表征。结果表明:Al-Ti-TiO2-Ho2O3系原位合成的Al2O3/TiAl复合材料由TiAl、Ti3Al、Al2O3以及HoAl3相组成;Ho2O3的引入对基体相生成比例(TiAl:Ti3Al)有一定的调控作用,并使得基体晶粒和Al2O3晶粒均有所细化且逐渐分布均匀。力学性能测试表明:当Ho2O3的引入量为6%时,材料的抗弯强度达到最大值,约为593.5MPa;断裂韧度达到最大值,为8.74MPa.m1/2,具有可接受的力学性能。Ho-doped Al2O3/TiAl composites were fabricated by in-situ reaction synthesis using the exothermic reaction of Al2O3/TiAl Ho2O3 system. In addition, DTA, XRD analysis for the exploration of their reaction course were adoped. The phase composition, microstrueture of crystal grain and performance of oxidation resistance were characterized by XRD, EDS and SEM. The results indicated that the phases of composite are composed of TiAI, Ti3Al, Al2O3 and HoAl3. The doping of He2O3 has a function to control and alter the phase proportion of the matrix （TiAl： Ti3Al）, and makes, the matrix and Al2O3 grains more refining with increasing holmium content. The mechanical property tests show that the addition of Ho2O3 could improve the properties of composites significantly. When the addition of Ho2O3 is 6%, the material shows acceptable mechanical properties： bending strength of 593.5MPa, fracture toughness of 8.74MPa · m^1/2.

关 键 词：Ho掺杂 原位反应 Al2O3-Ho2O3 /TiAl复合材料 微观形貌 力学性能 

分 类 号：TQ174.43[化学工程—陶瓷工业]