圓杯微深引伸成形製程之分析

An Analysis of the Micro Deep Drawing Process of Cylindrical Cup

李建輝(Chien-Hui Lee)

指導教授 ： 李經綸

淡江大學/工學院/機械與機電工程學系碩士班/碩士(2009年)

https://doi.org/10.6846/TKU.2009.00539

摘要

本文應用動顯函有限元素法進行圓杯微深引伸成形製程之分析，探討不同模具圓弧角對沖頭負荷與衝程關係、成形歷程、杯高分佈、應力分佈與塑性應變分佈，並將數值分析與實驗結果相比較，以驗證本文所用有限元素分析程式的可信度。
在實驗方面，首先依據ASTMD-412-F之規範，進行微拉伸試驗取得電解銅箔之材料參數，其最大真應力值約為359.99MPa，最大真應變值約為0.128。其次，參考ASTM-D1894規範進行摩擦力試驗取得動摩擦係數，沖頭與壓料板相對料片之動摩擦係數為0.111，沖模相對料片之動摩擦係數為0.102。最後本文設計六組不同尺寸之微深引伸模具，以進行圓杯微深引伸成形實驗，並與數值分析結果相比較。
經數值分析與實驗結果比較得知，最大沖頭負荷會隨著沖頭與沖模圓弧角增加而降低，降低沖模圓弧角可有效減少皺摺之發生，並避免於圓杯微深引伸時發生二次負荷。成形杯高則隨著沖頭圓弧角增加而增加，因此本文所使用之動顯函有限元素分析程式，可合理的模擬圓杯微深引伸成形製程。

關鍵字

動顯函有限元素法 ； 微深引伸 ； 微拉伸試驗 ； 摩擦力試驗

並列摘要

In this study, the dynamic-explicit finite element program was applied to analyze the forming process in the micro deep drawing of cylindrical cup. The present study discussed the relationship between punch load and punch stroke, the deformation history, distribution of height of cup, distribution of von Mises stress and strain for various arc radii of tools. The reliability of the finite element program could be proved by the comparison between numerical analysis and experiment.
There were three experiments for this study. First, the material parameter of electrolytic copper foil was obtained by micro-tensile test of ASTMD-412-F specification for experiment. The maximum true stress was about 359.99MPa and the maximum true strain value was 0.128. Then, the kinetic friction coefficient was obtained by the friction test of ASTM-D1894 specification. The kinetic friction coefficient of punch and holder relative to blank was 0.111, and the one of die relative to blank was 0.102. Finally, the six different geometric sizes of tools were designed to compare with numerical analysis results for experiment of micro deep drawing of cylindrical cup in this study.
According to the comparison results between numerical analysis and experiment, the maximum punch load decreased as the arc radius of punch increased. When the arc radius of die decreased, the wrinkles of workpecies decreased, and the second load disappeared during the micro deep drawing process of cylindrical cup. The height of cup increased as the arc radius of punch increased. The dynamic-explicit finite element program could simulate the micro deep drawing of cylindrical cup reasonably in this study.

並列關鍵字

Dynamic-explicit finite element program ； Micro deep drawing ； Micro-tensile test ； Friction test

參考文獻

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