Net shape process from prealloyed powder has become a viable approach to manufacture high-performance, complex shaped titanium alloy components. In this work densification of Ti-5Al-2. 5Sn powder compacts in mild steel containers by means of hot isostatic pressing was studied. Due to the shielding effect of the container, inhomogeneous deformation of Ti-5Al-2. 5Sn powder compacts was observed during the experiment and this was also predicted by a finite element analysis. The mechanical properties of powder metallurgy ( PM) Ti-5Al-2. 5Sn alloy with different densities were compared. Near-net-shape forming processes of PM titanium alloy parts were studied. By using metal capsules and metal internal tooling, near-net-shaping of PM parts with complex shapes was demonstrated. The design of capsules and tooling was found very important because of the different shrinkage ratio of the differently shaped regions of the component.%粉末冶金近净成形工艺能够制备性能要求高、结构复杂的钛合金构件.将洁净Ti -5Al -2.5Sn预合金粉末封装在低碳钢材料制造的包套中,采用热等静压进行了粉体的致密化,研究了粉末在热等静压过程中的致密化行为.由于包套对热等静压压力的屏蔽效应,致密化过程后观察到了粉末/包套体的不均匀变形;通过有限元仿真也预测到包套对包套对热等静压压力的屏蔽效应引起的粉末/包套体的不均匀变形.对比了不同致密化成都的粉末合金的力学性能.采用粉末冶金近净成形技术制备了形状复杂的钛合金构件.研究发现,金属包套及内部金属型芯模具的设计非常重要,因为在零件的不同部位粉末/包套体在致密化进程中的收缩比例不尽相同.
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