Hot Compression Deformation Behavior and Microstructural Evolution of Al-7.5Zn-1.5Mg-0.2Cu-0.2Zr Alloy

Abstract:

Hot compression tests of as-homogenized Al-7.5Zn-1.5Mg-0.2Cu-0.2Zr alloy were carried out on Gleeble-3500 thermal simulation machine at the temperature ranging from 350°C to 550°C and strain rate ranging from 0.001s^-1 to 10s^-1. Processing maps were established on the basis of dynamic material model, and the microstructure was studied using electron back scattered diffraction (EBSD) technique. The results showed that the peak stress and steady flow stress decrease with decreasing strain rate or increasing deformation temperature. There are one peak efficiency domain and one flow instability domain in the processing maps. The flow instability domain which exists in high-strain-rate region becomes larger with increasing strain. Shear bands occur at 45° toward the compression axis at grain interiors and meanwhile flow localization occurs. The optimum deformation temperature and strain rate ranges from 450°C to 500°C and 0.003s^-1 to 0.1s^-1, respectively, with high power dissipation efficiency of 34-39%.

• Periodical: Materials Science Forum (Volume 913)
• Pages: 43-48
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.913.43
• Online since: February 2018
• Authors: Jian Liang He, Da Tong Zhang*, Wen Zhang, Cheng Qiu
• Keywords: Al-7.5Zn-1.5Mg-0.2Cu-0.2Zr Alloy, Hot Deformation, Microstructure, Processing Map

References

[1] E. A. Starke, J. T. Staley, Application of modern aluminum alloys to aircraft, J. Progr. Aerosp. Sci. 32 (1996) 131-172.

[2] B. Liu, C. Q. Peng, R. C. Wang, et al., Recent development and prospects for giant plane aluminum alloys, J. Chin J. Nonferrous Met. 20 (2010) 1705-1715.

[3] Y. V. R. K. Prasad, H. L. Gegel, S. M. Doraivelu et al., Modeling of dynamic material behavior in hot deformation: Forging of Ti-6242, J. Metall. Mater. Trans. A 15 (1984) 1883-1892.

DOI: 10.1007/bf02664902

[4] F. Zhang, J. L. Sun, J. Shen, et al., Flow behavior and processing maps of 2099 alloy, J. Mater. Sci. Eng. A 613 (2014) 141-147.

[5] H. Yin, H. Li, X. Su, et al., Processing maps and microstructural evolution of isothermal compressed Al-Cu-Li alloy, J. Mater. Sci. Eng. A 586 (2013) 115-122.

DOI: 10.1016/j.msea.2013.07.084

[6] Y. V. R. K. Prasad, T. Seshacharyulu, Processing maps for hot working of titanium alloys, J. Mater. Sci. Eng. A 243 (1998) 82-88.

DOI: 10.1016/s0921-5093(97)00782-x

[7] Y. V. R. K. Prasad, K. P. Rao, Processing maps and rate controlling mechanisms of hot deformation of electrolytic tough pitch copper in the temperature range 300-950°C, J. Mater. Sci. Eng. A 391 (2005) 141-150.

DOI: 10.1016/j.msea.2004.08.049

[8] O. Sivakesavam, Y. V. R. K. Prasad. Hot deformation behaviour of as-cast Mg-2Zn-1Mn alloy in compression: a study with processing map, J. Mater. Sci. Eng. A 362 (2003) 118-124.

DOI: 10.1016/s0921-5093(03)00296-x

[9] Y. V. R. K. Prasad, K. P. Rao. Processing maps for hot deformation of rolled AZ31 magnesium alloy plate: Anisotropy of hot workability, J. Mater. Sci. Eng. A 487 (2008) 316-327.

DOI: 10.1016/j.msea.2007.10.038

[10] Y. V. R. K. Prasad, K. P. Rao. Effect of homogenization on the hot deformation behavior of cast AZ31 magnesium alloy, J. Mater. Des. 30 (2009) 3723-3730.

DOI: 10.1016/j.matdes.2009.02.006

[11] D. Feng, X. M. Zhang, S. D. Liu, et al., Constitutive equation and hot deformation behavior of homogenized Al-7. 68Zn-2. 12Mg-1. 98Cu-0. 12Zr alloy during compression at elevated temperature, J. Mater. Sci. Eng. A 608 (2014) 63-72.

DOI: 10.1016/j.msea.2014.04.055