Some factors affecting the creep behaviour of metallic materials processed by equal-channel angular pressing

Abstract Very few reports describing the creep behaviour of materials processed by equal-channel angular pressing (ECAP) have shown that there are both similarities and differences between the creep behaviour of coarse-grained metals and alloys and their ultrafine-grained counterparts. This paper examines these differences and evaluates some factors affecting the creep behaviour of pure aluminium, pure copper, and the binary Al-0.2 wt.% Sc alloy processed by ECAP. It was found that the creep behaviour of pressed material depends strongly on the number of ECAP passes and successive passes result in a gradual decrease in the creep resistance which may be attributed to microstructural changes, homogenization of the microstructure and the microtexture, nanoporosity induced by the ECAP procedure and thermal instability of the pressed material during creep exposure.