2219铝合金VPPA焊缝断裂韧性研究

摘要

针对2219铝合金低匹配VPPA焊缝力学性能降低的问题，以裂纹尖端张开位移（CTOD）为表征参量，开展焊缝断裂韧度试验。结果表明，2219铝合金VPPA焊缝断裂属于弹塑性断裂，常温试验条件下，2219VPPA焊缝的CTOD值为0.089～0.164mm ，δ0.2BL值为0.084mm，焊缝金属表现了良好的断裂韧性；母材断口为脆性断裂，VPPA焊缝断口为塑性断裂，韧窝中强化相质点为Al2Cu。%According to the problem of the mechanical properties decreasing for undermatched 2219Al VPPA joints, the fracture toughness test of joints was carried out with the crack tip opening displacement (CTOD) as characteristic parameters. The results showed that, for the 2219Al VPPA joints, the failure pattern was the elastic-plastic fracture and the CTOD value was 0.089~0.164mm under test conditions at room temperature. The weld metal exhibited excellent fracture toughness with the δ0.2BL value of 0.084mm. The fracture surface of parent material was brittle fracture, while the plastic fracture was found in the fracture surface of VPPA joints with the strengthening phase particles Al2Cu in dimples.