Processing map for hot working of SiCp/7075 Al composites
(1. Department of Manufacturing Engineering, Annamalai University, Annamalai Nagar, 608002, India;
2. Department of Mechanical Engineering, Birla Institute of Technology and Sciences, Dubai)
2. Department of Mechanical Engineering, Birla Institute of Technology and Sciences, Dubai)
Abstract: The hot deformation behaviour of 7075 aluminium alloy reinforced with 10% of SiC particles was studied by employing both ‘‘processing maps’’ and microstructural observations. The composite was characterized by employing optical microscope to evaluate the microstructural transformations and instability phenomena. The material investigated was deformed by compression in the temperature and strain rate ranges of 300−500 ℃ and 0.001−1.0 s−1, respectively. The deformation efficiency was calculated by strain rate sensitivity (m) values obtained by hot compression tests. The power dissipation efficiency and instability parameters were evaluated and processing maps were constructed for strain of 0.5. The optimum domains and instability zone were obtained for the composites. The optimum processing conditions are obtained in the strain rate range of 0.1−0.9 s−1 and temperature range of 390−440 ℃ with the efficiency of 30%.
Key words: hot deformation; processing maps; recrystallization; flow instability