Effect of tensile straining on the precipitation and dislocation behavior of AA7075T7352 aluminum alloy

Abstract

The effect of tensile straining on the precipitation and dislocation behavior of the over-aged 7075 aluminum alloy at T7352 temper have been investigated. Microstructures depict dissolution of the precipitates at low tensile straining but reprecipitation occurs at a higher amount of strain. Such precipitation improves the resistance against stress-corrosion cracking as well as other mechanical properties. Detailed characterization displayed the formation of dislocation loops, forest dislocation along with tangled dislocations at a low amount of straining corresponding to a true strain of ~0.02. In contrast, low-density, high-density Taylor lattices, and dislocation cell structures were seen at higher true straining of 0.06, and 0.1 respectively. Dissolution, reprecipitation of second phases, changes in orientation, and development of dislocation structures are contributing to the two-slope deformation behavior of AA7075T7352 alloy.