鈦合金管彎曲成形之模擬分析

一般管件彎曲成形會造成一些幾何上的缺陷，尤其對於高強度的管件容易產生明顯的回彈現象，所以本文針對Ti-2Al-2.5Zr鈦合金探討回彈量及減薄率以改善彎管尺寸的準確度及管件承受內壓的能力。為了能提高彎管的精度，選擇正確的成形參數為重要的考量，所以在此以有線元素分析技術針對∅10×t1鈦合金管做彎曲成形模擬分析，並且搭配田口法(Taguchi Methods)做實驗設計，其中有12個因子，各因子包含3個水準，利用L_27 (3^13 )直交表進行27組模擬分析，並且經由望小之訊號雜訊比(S/N ratios)得知最佳製程參數組合。本個案研究結果顯示影響回彈量程度依序為：材料性質、彎曲半徑、助推速度、心軸伸出量、彎曲模與管子摩擦係數、壓模與管子間隙、壓模與管子摩擦係數。而影響減薄率依序為：彎曲半徑、心軸伸出量、助推速度、材料性質、壓模與管子間隙。最後經過逼近理想解排序法TOPSIS(Technique for Order Preference by Similarity to Ideal Solution)分析找出回彈量及減薄率多品質的最佳化製程參數，結果顯示最佳化製程參數可比原始製程參數之回彈量減少8.57%，減薄率之百分比減少6.83%。

關鍵字

彎管成形；鈦合金管Ti-2Al-2.5Zr ；有限元素分析；田口法

並列摘要

In general the bending of tubes will cause some geometric imperfections, especially for a high-strength tubes significant springback will occur after the unloading procedure. The aim of this paper is investigating springback and wall thickness reduction rate of Ti-2Al-2.5Zr titanium alloy tubes in order to improve the precision of specification and ability of bearing internal pressure. To achieve a precise bending deformation, the various forming conditions are important. This paper is based on a ∅10×t1 titanium alloy tube model, established by finite element analysis and uses Taguchi methods to do experimental design which has twelve control factors, each factor includes appropriate levels. The simulation analysis was used to analyze these twelve experiments of L_27 (3^13 ) orthogonal array and uses small the best characteristic of the signal to noise ratio that search the optimized combination of process parameters. The results showed that 1) Material property, the bending radius, relative boosting velocity, mandrel protrusion length, friction coefficient between bending die and tube, clearance between pressure die and tube and friction coefficient between pressure die and tube have a significant influence on springback. 2) Bending radius, mandrel protrusion length, relative boosting velocity, material property, clearance between pressure die and tube have a significant influence on wall thickness reduction rate. 3) After use TOPSIS evaluate method, reduce springback 8.57% and the percentage reduction in the rate of wall thickness reduction rate of 6.83%.

並列關鍵字

Tube Bending Forming ； Ti-2Al-2.5Zr Titanium ； FEM ； Taguchi Methods

參考文獻

[2] 韓明傑，迴轉彎曲法之彎管成形有限元素分析之探討，中興大學機械工程學系所，台中、台灣， 2008

[5] H. LI, K.P. SHI, H. YANG, Y.L. TIAN, Springback law of thin-walled 6061-T4 Al-alloy tube upon bending, Transactions of Nonferrous Metals Society of China, Vol. 22, pp. 357-363, 2012

[8] H. Li, H. Yang, F.F. Song, M. Zhan, G.J. Li, Springback characterization and behaviors of high-strength Ti–3Al–2.5V tube in cold rotary draw bending, Journal of Materials Processing Technology, Vol. 212, pp. 1973-1987, 2012

[11] Z.Q.Jiang,H.Yang, M. Zhan, Y.B.Yue, J.Liu, X.D.Xu, G.J.Li Establishment of a 3D FE model for the bending of a titanium alloy tube, International Journal of Mechanical Sciences, Vol.52, pp1115-11124, 2010

[12] R.J. Gu, H. YangM. Zhan, H. Li, H.W. Li, Research on the springback of thin-walled tube NC bending based on the numerical simulation of the whole process, Computational Materials Science, Vol.42, pp.537-549, 2008

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鈦合金管彎曲成形之模擬分析

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