Analysis of the effect of the hot stamping process on mechanical properties of 7075 aluminum alloy sheet

Document Type : Original Article

Authors

1 PhD Student, Faculty of Mechanical Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran

2 Associate Professor, Faculty of Mechanical Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran

3 Professor, Faculty of Materials and Metallurgical Engineering, Amirkabir University of Technology, Tehran, Iran

4 Assistant Professor, Department of Mechanical Engineering, Technical and Vocational University, Tehran, Iran

10.22034/ijme.2023.424240.1872

Abstract

7075 aluminum alloy, with a high strength-to-weight ratio and good impact strength, is one of the useful materials in the aerospace and automotive industries. However, this alloy has limitations such as poor formability, high spring back at low temperatures, and thermal distortion during hot forming. To overcome these limitations, a thermomechanical process including solution heat treatment, forming, and quenching in the die can be used. In this research, for producing a U-shape part with a depth of 30 mm, a 7075 sheet with a thickness of 2 mm was first subjected to solution heat treatment at a temperature of 480 ℃, and then was immediately transferred to a cooling die to be formed at a temperature of 4 ℃ under a hold time of 20 seconds. Finally, the part was artificially aged to improve its mechanical properties. A finite element simulation of the process using the ABAQUS software was also performed. Good dimensional accuracy and absence of rupture in the final U part, close agreement between the experimental and simulation results, an acceptable 25% reduction in elongation, very close tensile strength to the base material, and microhardness equal to 95% of the base material are the results of this research.

Keywords

References

[1] Dorward R C, Pritchett T R. Advanced Aluminium Alloys for Aircraft and Aerospace Applications. Materials & Design. 1988 March–April 9(2): pp. 63–69. doi: 10.1016/0261-3069(88)90076-3
[2] Brown KR, Venie MS, Woods RA. The increasing use of aluminum in automotive applications, The journal of the Minerals, Metals and Materials Society. 1995 47:20-23. doi: 10.1007/BF03221224
[3] Zheng K, Li Y, Yang S, Fu K, Zheng J, He Z, Yuan S. Investigation and Modeling of the Preheating Effects on Precipitation and Hot Flow Behavior for Forming High Strength AA7075 at Elevated Temperatures. Journal of Manufacturing and Materials Processing. 2020 July 4(3): 76. doi: 10.3390/jmmp4030076  
[4] Tohidi Manesh R, Ghobeiti Hasab M, Heidary Moghadam A. Composite fabrication and surface reinforcement of aluminum 7075 by pumice micro and nanoparticles using the friction stir process (FSP). Iranian Journal of Manufacturing Engineering. 2020 7(5):56- 63. [In Persian]
[5] Miller WS, Zhuang L, Bottema J, Wittebrood AJ, De Smet P, Haszler A, Vieregge A. Recent development in aluminium alloys for the automotive industry. Materials Science and Engineering: A. 2000 March 15;280(1):37-49. doi: 10.1016/S0921-5093(99)00653-X
[6] Mendiguren J, Ortubay R, de Argandoña ES, Galdos L. Experimental characterization of the heat transfer coefficient under different close loop-controlled pressures and die temperatures. Applied Thermal Engineering. 2016 99:813–824. doi: 10.1016/j.applthermaleng.2016.01.133
[7] Harrison NR, Luckey SG. Hot Stamping of a B-Pillar Outer from High Strength Aluminum Sheet AA7075. SAE International Journal of Materials and Manufacturing. 2014 7(3):567-573.
[8] Wróbel I, Skowronek A, Grajcar A. A Review on Hot Stamping of Advanced High-Strength Steels: Technological-Metallurgical Aspects and Numerical Simulation. Symmetry. 2022 14(5): 969. doi: 10.3390/sym14050969
[9] Mohamed S M, Alistair D F, Jianguo L, Daniel S B, Trevor A D. Investigation of deformation and failure features in hot stamping of AA6082: Experimentation and modelling. International Journal of Machine Tools and Manufacture. 2012 53(1):27–38. doi: 10.1016/j.ijmachtools.2011.07.005
[10] Degner J, Horn A, Merklein M. Experimental study on the warm forming and quenching behavior for hot stamping of high-strength aluminum alloys. IOP Conf. Series: Journal of Physics: Conf. Series 2017 896 012055. doi: 10.1088/1742-6596/896/1/012055
[11] Xiao W, Wang B, Zheng K. An experimental and numerical investigation on the formability of AA7075 sheet in hot stamping condition. The International Journal of Advanced Manufacturing Technology. 2017 April 21; 92:3299-3309. doi: 10.1007/s00170-017-0419-6
[12] Kumar M, Ross NG. Investigations on the hot stamping of AW-7921-T4 Alloy Sheet. Advances in Materials Science and Engineering. 2017 Feb 26; 2017:1–10. doi: 10.1155/2017/7679219
[13] Mendiguren J, Saenz E, Argandoña de, Galdos L. Hot stamping of AA7075 aluminum sheets. IOP Conf. Series: Materials Science and Engineering. 2016 159 012026. Mondragon Spain. doi: 10.1088/1757899X/159/1/012026
[14] Wang H, Luo Y, Friedman P, Chen M, GAO L. Warm forming behavior of high strength aluminum alloy AA7075. Transactions of Nonferrous Metals Society of China. 2012 22(1):1-7. doi: 10.1016/S1003-6326(11)61131-X
[15] Wright D, Henshaw J, Harrison N, and Luckey S. Stress-Corrosion Cracking Evaluation of Hot Stamped AA7075-T6 B-Pillars. SAE International Journal of Engines. 2017 10(4):2021-2026. doi: 10.4271/2017-01-1271
[16] Idrees U, Ahmad S, Shah IA, Talha M, Shehzad R, Amjad M, Rahiamin Koloor SS. Finite element analysis of car frame frontal crash using lightweight materials. 2023 Journal of Engineering Research. 11 (2023) 100007. doi: 10.1016/j.jer.2023.100007
[17] Ma Z, Ji H, Huang X, Xiao W, Tang X. Research on High Temperature Stamping Forming Performance and Process Parameters Optimization of 7075 Aluminum Alloy. Materials. 2021 14(19), 5485. doi: 10.3390/ma14195485
[18] Abdolazizi A, Fallahi A. Effect of ECAP and Heat treatment on Mechanical properties of 7075 Al Alloy. Iranian Journal of Manufacturing Engineering. 2016 3(2):1-10. [In Persian]

Files

Share

How to cite

Statistics