Influence of Thermal Deformation Parameters on Mechanical Properties and Microstructure Evolution of AA7075 Aluminum Alloy during Hot Stamping-Quenching Process
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Hot tensile tests have been performed on AA7075 aluminum alloy to investigate the effects of temperature and strain rate on its deformation behavior during the hot stamping-quenching process. The corresponding mechanical properties and associated microstructures have also been studied. The results indicate that the flow behavior curves exhibit work hardening, a dynamic equilibrium, then a dramatic decrease, ultimately leading to fracture. Ductility of over 30% can be obtained at relatively low deformation temperature and strain rate. The fracture mechanism changes from ductile transgranular fracture to ductile intergranular fracture owing to the weakening of the grain-boundary strength at high temperatures. The strength of the tested samples after artificial aging treatment increases with the deformation temperature after solid-solution heat treatment. It is more appropriate to choose a temperature of 400°C and a strain rate of 0.1–1 s−1 for AA7075 aluminum alloy parts to simultaneously obtain the desired ductility and final strength in this process.
This work is financially supported by the National Natural Science Foundation of China (U1564202), the National Natural Science Foundation of China (Grant No. 51405358 and 51775397), the 111 Project (B17034), the Outstanding Young and Middle-aged Science and Technology Innovation Team Plan of Hubei Provincial Department of Education (No. T201629), and the Innovative Research Team Development Program of Ministry of Education of China (IRT13087), who the authors gratefully thank with sincere appreciation.
- 11.N.R. Harrison, S.G. Luckey, and S.A.E. Int, J. Mater. Manuf. 7, 567 (2014).Google Scholar
- 16.R. Jafari Nedoushan, M. Farzin, M. Mashayekhi, and D. Banabic, Metall. Trans. 43, 4266 (2012).Google Scholar
- 17.J. Cai, Modelling of phase transformation in hot stamping of boron steel (London: Imperial College London, 2011).Google Scholar
- 18.H. Zhao, Y. Quan, Z. Zhang, and L. Lin, J. Funct. Mater. 596, 176 (2014).Google Scholar
- 23.W.Y. Liu, Research on mechanical property and microstructure evolution in hot working of 7085 aluminum alloy (Chongqing: Chongqing University, 2014).Google Scholar
- 26.X. Fan, Forming behavior and strengthening mechanism for integrated process of hot deformation-quenching of 2195 Al-Li alloy sheet (Harbin: Harbin Institute of Technology, 2016).Google Scholar
- 35.R.W. Cahn, P. Haasen, E.J. Kramer, and W. Schröter, Materials Science and Technology (Weinheim: Wiley, 1991).Google Scholar
- 36.R. Chen, Q. Xu, and B. Liu, Acta Mater. Sin. 52, 987 (2016).Google Scholar
- 37.A.P. David, E.E. Kenneth, and Y.S. Mohamed, Phase transformations in metals alloy, 3rd ed. (London: CRC Press, 2014).Google Scholar