Effect of Dispersed Phases on Cyclic Softening of Al-Cu Alloys with GP Zones.

摘要

The micro-mechanism responsible for cyclic softening is dependent on both the microstructure and the strain range. The smaller cyclic softening was observed for the 6.3 w/o Cu alloy compared to the 3.6 w/o Cu alloy at 0.4% strain amplitude. This is attributed to the large theta particles which cause the plastic deformation to be lses localized. Disordering of the structure evidently occurs at higher strain amplitudes. The distribution of both the dispersoids and inclusions in 2024 is more effective in preventing cyclic softening than the theta particles in the 6.3 w/o Cu alloy. It is absent at all strain ranges tested. (Author)