Anisotropy of Intermetallic Particle Cracking Damage Evolution in an Al-Mg-Si Base Wrought Aluminum Alloy under Uniaxial Compression

摘要

Particle cracking is an important damage mode in numerous engineering alloys having anisotropic microstructures. In this contribution, cracking of anisotropic Fe-rich intermetallic particles in an extruded 6061 (T651) Al-alloy is quantitatively characterized as a function of compressive strain for two loading directions. The Fe-rich intermetallic particles rotate when a compressive load is applied parallel to the extrusion direction, which in turn affects the particle cracking process. At low compressive strains, the number fraction of cracked Fe-rich particles is higher in specimens loaded perpendicular to the extrusion axis as compared to that in specimens loaded parallel to the extrusion axis. However, the reverse is true at the high strain levels. These differences in damage evolution are explained on the basis of particle rotations and microstructural anisotropy.