(北京航空航天大学机械工程及自动化学院 航空宇航制造工程系，北京100191)
摘 要: 通过数值模拟和热等静压实验，研究包套在铝合金粉末热等静压成形过程的屏蔽效应及其对性能的影响，建立包套对等静压力屏蔽效应的关系公式。结果表明：包套对等静压力的屏蔽效应与包套的几何尺寸、壁厚、屈服强度有关系，包套越厚，其屏蔽效应越显著，降低热等静压过程中粉末颗粒重排阶段的致密化程度。由于包套的屏蔽，对于二元共晶和三元共晶的液相没有实现完全挤出，在粉末颗粒与颗粒交界处残留有没有被液相填充完全的孔隙，降低粉末件最终的致密度。当包套厚度较大时，降低了粉末铝合金材料的抗拉强度和屈服强度，而对材料塑性的影响不明显。
关键字: 铝合金粉末；热等静压；屏蔽效应
（Manufacture Engineering of Aerospace Vehicle, School of Mechanical Engineering and Automation,
Beihang University, Beijing 100191, China）
Abstract:By numerical simulation and hot isostatic pressing (HIP) tests of aluminum alloy powders, the shielding effect of capsules and its impact on the mechanical properties of P/M aluminium alloys were studied during the processes of HIP. In addition, the experimental equations about the shielding effect of capsules were established. The results show that the shielding effect of capsules depends on geometry size of capsule, wall thickness and yield strength. The thicker the capsule, the greater the shielding effect of capsule, which reduces densification during grains rearrangement stage in the processes of HIP. Binary eutectic liquid phase and ternary eutectic liquid phase would not be squeezed out and the pores among powder particles are not filled by the liquid phase because of the shielding effect of capsule. Besides, through tensile mechanical properties tests, the tensile strength and yield strength of P/M aluminium alloys increase when the capsule becomes thin but the effect on the metal plastic is insignificant.
Key words: aluminum alloy powder; hot isostatic pressing; shielding effect
