Deformation map for hot working of AA2024 composites reinforced with SiC particle

The dynamic deformation behavior of Al 2024 composites reinforced with 1 and 8 μm SiCp (15 vol.%) has been investigated in the temperature range of 370 to 500°C and strain rate range of 0.1 to 3.0/sec by torsion testing. Processing maps showing the variation of the efficiency of power dissipation expressed by [2m/(m+l)], where m is the strain rate sensitivity, with temperature and strain rate have been described for the composites. Also, the domain of dynamic recrystallization (DRX) and peak efficiency of the composites were analyzed to suggest an optimum hot working condition for DRX. The SiCp/A12024 composite with 8 (μm SiCp showed 40% efficiency at the DRX domain (370~460°C, 0.1~0.5/sec). The optimum temperature and strain rate condition for the DRX of the composites is 430~450°C and 0.5/sec. The characteristics of these results were discussed with the help of microstructural observation during hot deformation. This article based on a presentation made in the symposium “The 1^st Korea—Japan Structural Dynamic Symposium”, held at Sunchon National University, Sunchon, Korea, August 5–8, 1999 under the auspices of The Korean Insitute of Metals and Materials and Research and Development Center for Automobile Parts and Materials.