Effect of microstructure on hot tensile deformation behavior of 7075 alloy sheet fabricated by twin roll casting

7075 aluminum alloy sheet with a thickness of 1 mm was successfully fabricated by twin roll casting and subsequent rolling process. The hot tensile deformation behavior of 7075 alloy was evaluated and large elongation over 200% was obtained at 450 °C under the high strain rate of 1×10−1 s−1. In order to clarify the reason for the large elongation obtained at high strain rate, the effects of microstructure on hot tensile deformation behavior were investigated. The results show that high solidification rate during TRC casting process induced small particles (~1 μm) in homogeneous distribution. The relatively high fraction of particles over 1 μm in size attributed the homogeneous recrystallized microstructure with fine grains induced by particle simulated nucleation (PSN). This fully recrystallized fine-grained microstructure of TRC alloy sheet contributed to high ductility and formability of 7075 alloy sheet under high strain rate.