Deformation behaviors of porous 4032 Al alloy preform prepared by spray deposition during hot rolling

Abstract

Rolling processing was selected to produce fully dense sheet from porous preform. Deformation behavior of the porous preform prepared by spray deposition during hot densification rolling has been investigated. The strain distribution in the deformation zone of the porous samples is analyzed. A notable deformation behavior is that the thickness reduction of the porous preform decreases from the surface to the center across the section, even though the total thickness reduction is up to 40% in a single pass, which is obviously different from the deformation characteristic of the fully dense metal. A decreased normal stress from surface to center and a lower work hardening effect during rolling of porous metal are supposed to be the main factors. When the longitudinal and transverse flow during rolling were retarded by contact friction, a decreased strain in length and width will result in a decreased thickness strain during rolling of fully dense metal due to a constant volume. However, the porous preforms tend to be compacted firstly near the surface of porous metal due to porosity.