Optimization of Axisymmetric Extrusion Die Profiles
Subject Areas : Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering
1 - دانشیار، دانشکده مکانیک ، دانشگاه آزاد اسلامی واحد خمینی شهر.
2 - مربی، گروه مکانیک ، دانشگاه آزاد اسلامی واحد کردکوی
Keywords: Optimization, Finite Element Method, Extrusion, Bezier curves, Constant strain rate,
Abstract :
In this research, optimization process of axisymmetric extrusion dies is proposed. Plastic zone is analyzed using finite element method in the Eulerian system with flow formulation. The die profiles are defined by Bezier curves with six control points. Two effective functions are considered in this research; standard deviation of the strain rate and the rate of energy consumption during extrusion process. A coupled numerical approach of finite element analysis in Eulerian system and the non-gradient Nelder-Mead method is utilized to determine optimum die profiles. Results show that optimized die has higher uniformity in strain rate distribution and less strain values with respect to the non-optimum conical die. In the case of minimizing energy consumption rate, results show that for the die with constant and variable lengths and low friction, the die profile tends to the stream line. In die with variable length and high friction, friction has more effective role in optimization and the die length tends towards lower lengths during optimization.
[1] Mihelic A. Stok B., Tool design optimization in extrusion processes, Computers & Structures, Vol. 68, 1998, pp. 283-293.
[2] Lee S.K., Ko D.C. Kim B.M., Optimal die profile design for uniform microstructure in hot extrusion product, International Journal of Machine Tool Manufacturing, Vol. 40, 2000, pp 1457–1478.
[3] Kim N. H., Kang C. G., Kim B.M., Die design optimization for axisymmetric hot extrusion of metal matrix composites, International Journal of Mechanical Sciences, Vol. 42, 2000, pp. 1507-1520.
[4] Ulysse P., Extrusion die design for flow balance using FE and optimization methods, International Journal of Mechanical Sciences, Vol. 44, 2002, pp. 319–341.
[5] Juchen X., Xinyun W., Lin Z., Guoan H Optimization of die profile for improving die life in the hot extrusion process, Journal of Materials Processing Technology, Vol. 142, 2003, pp. 659–664.
[6] Yan H., Xia J, An approach to the optimal design of technological parameters in the profile extrusion process, Science and Technology of Advanced Materials, Vol. 7, 2006, pp. 127–131.
[7] Xianghong W., Guoqun Z., Yiguo L, Xinwu M., Numerical simulation and die structure optimization of an aluminum rectangular hollow pipe extrusion process, Materials Science and Engineering A 435–436, 2006, pp. 266-274.
[8] Gordona W. A., Van Tyneb C.J., Moon Y. H., Axisymmetric extrusion through adaptive dies- Part 3: Minimum pressure streamlined die shapes, International Journal of Mechanical Sciences, Vol. 49, 2007, pp. 104-115.
[9] Bakhshi-Jooybari M., Saboori M., Noorani-Azad M., Hosseinipour S. J., Combined upper bound and slab method, finite element and experimental study of optimal die profile in extrusion, Materials and Design, Vol. 28, 2007, pp. 1812-1818.
[10] Dixit P. M., Dixit U. S., Modeling of Metal Forming and Machining Processes, Springer, London, 2008.
[11] Altan T., Oh S.I., Gegel H.L., Metal Forming Ð Fundamentals and Applications, American Society of Metals, Cleveland, OH, 1983.
[12] Saxena A., Sahay B., Computer Aided Engineering Design, Springer, 2005.
[13] Himmelblau D.M., Applied Nonlinear Programming, McGraw-Hill, New York, 1972.
[14] Hosford W. F., Caddell R. M., Metal Forming: Mechanics and Metallurgy Cambridge University Press, 2007.