Finite Element Analysis of Asymmetric Extrusion of Aluminum-Alloy

• Main Authors: Chun-Ming Hong, 洪俊銘
• Other Authors: 陳復國
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/16302191486901206412

碩士 === 臺灣大學 === 機械工程學研究所 === 95 === The superior properties of aluminum-alloy draw attentions from the light-trend industry recently. The principal manufacturing process of the asymmetric hollow products of A7075 aluminum-alloy has been extruded by using porthole dies. However, there are usually bending and torsion defects on the hollow products. Therefore the extrusion process of asymmetric aluminum-alloy products is studied in the present study by the finite element analysis and experiments. The finite element software DEFORM is employed to simulate the extrusion processes of asymmetric products. Due to the software DEFORM is not able to simulate welding directly, the problem is solved at first. Following the deformation of asymmetric products is studied. It shows the defects which are bending and torsion are caused by uneven material flow. In addition, another software HYPERXTRUDE is employed to compare simulation results with DEFORM. The experiment of asymmetric extrusion was practiced to verify the analyzed results. The experimental results obtained in the present study show good agreement with simulations. It shows the finite element software DEFORM is suitable to process asymmetric extrusion. The influence of important process parameters such as the temperature, extrusion speed, product thickness, m value, corner radius of bottom die are analyzed by simulations. According to the results of analysis, it shows the serious effect could be caused by corner radius of bottom die. Modifying the corner radius of bottom die indeed alters the material flow. Therefore, we can observe how the defect of profile changes under different material flow by changing the corner radius. In the end, Taguchi method is applied to make the optimum design of corner radius of bottom die. After optimized the corner radius design, the bending and torsion of original design is improved. The results of this study can be reference resources for related academic research and can also be used to develop related products for industry production.