Mechanical behavior of ultra-fine grained aluminum at different temperatures and strain rates

An available aluminum with a purity of more than 99.9% (mass fraction) was used to produce ultra-fine grained aluminium (UFG-Al) by equal channel angular pressing (ECAP) method. The mechanical behaviour of UFG-Al at temperatures ranging from 77 to 473 K under quasi-static and dynamic compression was investigated. The effects of grain refinement on the strain hardening behavior, temperature and strain rate sensitivities of mechanical properties of pure aluminum were studied. The grain refinement leads to the lost of stain hardening abilities, and the corresponding temperature and strain rate sensitivities also significantly increase. Meanwhile, as the temperature rises, the strain rate sensitivity of mechanical properties increases significantly.