Microstructural characteristics and superplastic-like behavior in aluminum powder alloy consolidated by equal-channel angular pressing

Experiments were conducted on 2024Al-3mass%Fe-5mass%Ni (3F5N) alloy powder to investigate the feasibility of producing a compaction with very homogeneous fine microstructure using equal-channel angular (ECA) pressing and of forging the compaction superplastically. It is shown that ECA pressing is capable of obtaining the compaction almost without pores and with very high hardness even after a single pressing. Repetitive pressings were conducted on the same samples, up to a total of three passages through a die, with the samples pressed without rotation (R = 0°) and after rotating through 90° or 180° between each pressing. The results suggest that ECA pressing with R = 90° rotation is most effective in producing a reasonably homogeneous microstructure consisting of fine intermetallic particles and equiaxed fine subgrains, and that such microstructure formation could contribute to the superplastic-like deformation behavior at high strain rate.