He Weijun

Deformation behaviors and processing maps of CNTs/Al alloy composite fabricated by flake powder metallurgy

Abstract Deformation behaviors of CNTs/Al alloy composite fabricated by the method of flake powder metallurgy were investigated by hot compression tests, which were performed in the temperature range of 300–550 °C and strain rate range of 0.001– 10 s −1 with Gleeble–3500 thermal simulator system. Processing maps of the CNTs/Al alloy at different strains were calculated to study the optimum processing domain. Microstructures before and after hot compressions were characterized by electron backscattered diffraction (EBSD) method. Stress–strain curves indicate that the flow stress increases with the increase of strain rate and the decrease of temperature. The processing maps of the CNTs/Al alloy at different strains show that the optimum processing domain is 500–550 °C, 10 s −1 for hot working. EBSD analysis demonstrates that fully dynamic recrystallization occurs in the optimum processing domain (high strainrate 10 s −1 ), whereas the main soften mechanism is dynamic recovery at low strain rate (0.001 s −1 ).