"Influence of the precipitation state on the thermal stability of severely deformed aluminum alloys"

A promising way to increase the strength of aluminum alloys is by grain refinement. Therefore the production of so-called ultra-fine grained (UFG) microstructures by severe plastic deformation (SPD) is a very interesting topic. One of the most common SPD processes is Equal Channel Angular Pressing (ECAP), which was compared to Confined Channel Die Pressing (CCDP) and cold rolling. In the focus of this work lays on the one hand the influence of different precipitation states on the formation of UFG structures and their influence on the mechanical properties and on the other hand it was examined if the thermal stability of these structures can be improved either by supersaturated solid solution(by impurity drag) or by precipitates (by grain boundary pinning). With a better understanding of the ongoing softening mechanisms a good combination of high strength and good ductility can be achievedby alternating SPD and heat treatment.