粉末冶金Ti-6Al-4V 的组织及形成机理

利用热等静压(HIP)技术及旋转电极粉,采用预合金粉工艺制备了全致密的粉末冶金Ti-6Al-4V合金,用光学显微镜对其金相组织进行了观察,分析其形成机理,并对粉末冶金Ti-6Al-4V合金的室温拉伸性能、弹性模量、冲击性能及断裂韧性进行了研究.结果表明:粉末冶金Ti-6Al-4V金相组织主要由条片α相+相间β相组成,有细小的等轴α相分布在晶粒界面处,包裹着条片α相,这种独特的组织状态是由制备工艺决定的,具有良好的综合性能.

Microstructure and Forming Mechanism of Powder Metallurgy Ti-6Al-4V

The prealloyed powder metallurgy(PM) process is studied in this paper to prepare PM Ti-6Al-4V alloy.And hot isostatic pressing(HIP) technology and the plasma rotating electrode processing(PREP) powders are used in the prealloyed processing to get full density material.The microstructures are examined by optical microscope,and the forming mechanism is studied.Room temperature tensile properties and elastic modulus and impact toughness and fracture toughness of PM Ti-6Al-4V alloy are tested and discussed.The results show that the typical microstructures of the PM Ti-6Al-4V alloy are platelet α + fine transformed β structure,surrounded by equiaxed α on boundaries of the grains.The special microstructure is formed by the reason of special prealloyed process and has excellent comprehensive properties.