Synchrotron radiation imaging and characterization of creep cracks in 2219 aluminum alloy

Abstract

Abstract Aluminum alloys are lucrative aerocraft materials due to their high-temperature performance, which involves creep crack propagation. However, it is difficult to acquire three-dimensional morphology, volume, and quantity through traditional imaging and characterization techniques, as metallic alloys are optically opaque. The development of synchrotron radiation X-ray tomography has facilitated the study of creep crack propagation. In this study, samples obtained by an interruption experiment were subjected to X-ray tomography observation. Based on reconstruction and visualization software analysis, cracks were first formed inside the material and then propagated via the growth and connection of creep voids. While propagating forward, the cracks also propagated toward the material surface, with the inside of the material propagating more than the surface of the material. When the main crack propagated, irregularly shaped microcracks and large independent branch cracks were generated, promoting the propagation of the main crack.