以有限元素分析暨田口式品質方法模擬高強度鋁合金銲合壓力與材料特性之研究

Study on Simulation Welding Pressure of High Strength Aluminum Alloy and Material Property by Finite Element Analysis and Taguchi Method

許光城(Quang-Cherng Hsu) ； 盛鉑灃(Bo-Feng Sheng) ； 陳仕諺(Shih-Yen Chen)

《鍛造》 22卷3期 (2013/10) Pp. 12-23

摘要

鋁合金7075強度高，廣泛用於航太與汽車等工業。雖然它擁有許多良好的機械性質，但其銲合性較差，較難運用擠伸製程製作結構用管件。本研究首先利用壓縮實驗獲得鋁合金7075材料之塑流應力，再將其匯入有限元素分析軟體DEFORM-3D並搭配田口式品質工程設計進行模擬以獲取最大銲合壓力，再將擠製出的中空方形管分成熱處理以及未熱處理兩種並進行拉伸試驗，最後進行模擬與實作的比較。由拉伸試驗結果得知經熱處理過後之7075中空方形管之抗拉強度約提升150MPa；綜合破斷面觀測、SEM觀測、拉伸試驗結果及第一年國科會計畫（NSC 100-2221-E-151-019-）結果比較可得知除了含有「色差模痕」之TYPE(2)第三邊外，本研究對於擠製高強度鋁合金7075之有縫管件可說相當成功，其未經熱處理之抗拉強度可達素材之86.7%；由模擬分析結果得知影響模具銲合壓力之主要因素為出口承面長度之貢獻值最高約55.9%、其次為軸心長度約為23.1%、再次之為（母模）導料室高度與長度比約為12.4%、最後為（公模）導料室圓角約為8.6%；由因子反應圖表獲得模具設計最佳化組合可提升銲合壓力達19.7%。

關鍵字

7075鋁合金 ； 銲合壓力 ； 破斷面 ； 田口 ； DEFORM-3D

並列摘要

Due to high strength and light weight characteristics, Aluminum alloy 7075 is widely used in aerospace and automobile industries. AA7075 has good mechanical properties, but its welding strength is poor and difficult to produce extruded hollow products. In this study, compression test was used to obtain material flow stress of AA7075, which was then imported into DEFORM 3D finite element analysis software. Together with Taguchi design method, the maximum welding pressure during hollow extrusion process was obtained. A suitable upper die and lower die for hollow extrusion were fabricated where the extruded products were divided into two categories, such as with and without T6 heat treatment. The tensile tests were conducted to investigated the welding strength for the above products. The results of tensile test show that the tensile strength after heat treatment is increasing about 150Mpa compared to without heat treatment. By over all checking on fracture surfaces, observed by SEM, tensile test results and the first year research results (NSC 100-2221-E-151-019-) and neglecting the results in the third side of TYPE(2) where the color difference mark happen, this study for the extruded high strength AA7075 is quite successful because the tensile strength up to 86.7% of the source material without heat treatment. The results of optimal simulation analysis indicated that the main factors affecting the die welding pressure is die bearing length which is about 55.9 percent, followed by the length of mandrel which is about 23.1 percent. The factor of response graph result shows that via optimal die design by Taguchi method the welding pressure can be increased about 19.7 percent.

並列關鍵字

Aluminum alloy 7075 ； Welding Pressure ； Fracture ； Taguchi Method ； DEFORM-3D