Role of dynamic precipitation on the strengthening mechanism of cryorolled 6063 Al alloy

Abstract

6063 Al alloys was cryorolled under solutionized (sample1) and peak aged condition (sample2) to study the role of dynamic precipitation on the strengthening mechanism. It is observed that in case of sample1 dislocations density is more compare to sample2. In the 1st case high angle sub grains (presence of high fraction of HAGBs) of less than 100 nm in size have been generated during cryorolling. In case of sample2, grains are aligned along the rolling direction. This is obvious that the higher densities of dislocations (in sample1) restrict the grain boundaries to be aligned along the rolling direction. Therefore, the grain boundaries are aligned along the rolling direction only in case of sample2. Whereas such type of alignments of grain boundaries are not observed in case of sample1. Presence of very fine grains along with high density of dislocations are responsible for attaining higher strength of sample1 compare to sample2.