以田口氏設計法做非對稱細薄實體擠型模具設計最佳化

The Optimization of Die Design in Non-symmetric Thin Solid Extrusion for the High Strength Aluminium by Taguchi Method

王水鐸(Wang, Shui-To) ； 詹振裕(Chan, Chen-Yu) ； 李榮顯(Lee, Rong-Shean)

《鍛造》 22卷3期 (2013/10) Pp. 6-11

摘要

在國內鋁擠型模具業，國內擠型模具產業大都屬中小企業，在模具設計製造上大多依賴實務經驗與試誤法則。尤其在面對高強度鋁合金非對稱細薄實體擠型（non-symmetric thin solid extrusion）時，其擠出產品嚴重彎曲變形，嚴重影響生產品質及效率，增加生產成本。高強度鋁合金非對稱細薄實體擠型之模具設計涉及三維模具幾何參數及胚料可成形性等製程參數的影響，國內擠型模具廠商之研發人力素質無法勝任複雜三維擠型模具幾何設計改良的任務。國內外迄今有採用上界限法來選定特定速度場及結合幾何函數最佳化方法以建立最佳化模具曲線面幾何設計，尚未有關於非對稱細薄幾何之擠型模具幾何最佳化設計之學術文獻。本文針對高強度鋁合金非對稱細薄實體擠型，採用田口氏設計法，以及採用DEFORM-3D套裝軟體進行有限元素法模擬分析，進行擠型預成形設計之最佳化，以解決高強度鋁合金擠出胚料彎曲變形之技術瓶頸。

並列摘要

The extrusion of high-strength aluminium is an important indispensable process which can produce the highly valuable products. Empirical knowledge and trial-and-error method are still common approaches used for die design in Taiwan's extrusion industry. However, the events of the unexpected severely distortion of the extruded products and unstable short service life of extrusion dies will often unfortunately occur, especially for non-symmetric solid extruded products of high-strength aluminium, which will clearly increases production cost and lowers efficiency. There are several concerned parameters of 3D geometry, material and process in the complicated non-symmetric thin extrusion. The upper-bound method and mathematic function approach have been used to obtain the optimal die geometry curve or surface model which can only to satisfy the die design about the axial-symmetric and simple 3D die profile. The execution of this proposal applied is an emergency desired mission for the domestic extrusion industry currently. This paper proposes a method for establishing optimal die design for non-symmetric thin soild extrusions using the Taguchi method and the finite element method. Taguchi's orthogonal array is applied to plan the simulation of FEM. After Taguchi's response analysis, the influence of each geometry factor on the plastic flow (velocity) was understood and an optimum die design was obtained. In order to resolve the critical issues of occurrence of out-of shape of the extruded products and having unstable short service life of the dies, the optimal design of pre-forming is the major works in the present project.