Microscopic Characteristics of Damage Evolution in Ultrapure Aluminum under Tensile Loading

A series of plate-experiments are carried out to acquire ultrapure aluminum (purity, 99.999%) samples with damage. Based on the metallographic of all "soft-recovered" samples, the characteristics of damage evolution and spallation damage mechanism in ultrapure aluminum are analyzed in detail. Results show that the damage will increase regularly with increasing loading strength. Most of voids appear in the grain boundary and grow alone under tensile loading before they coalesce each other to form big irregular voids. These analysis results are helpful to understand the evolution process of ductile metal dynamic fracture and establish the damage evolution model.