以鍛粗加工實驗驗證變分上界限法

Experimental Verification of The Variational Upper-Bound Method Using Upset forging Tests

洪嘉駿(Jia-Jyun Hong)

指導教授 ： 葉維磬

國立中央大學/工學院/機械工程學系/碩士(2007年)

摘要

本文以鋁6061圓棒為試片材料，做一系列鍛粗加工實驗，藉由蝕刻在試片表面的網格節點的位移觀察經鍛粗後的材料塑性變形行為，包含接觸界面的摩擦係數（Friction）與桶脹輪廓（Bulging）的量測。本文所採用之試片幾何形狀，包含圓柱狀與圓環狀。本文之量測主要係將鍛粗後之試片置於CCD工具顯微鏡下，經高倍率放大後配合精密的X-Y平台以量測網格節點的座標位置。根據網格節點在鍛粗成形前、後的位置座標可進一步計算出材料變形過程的流動速度場以及桶脹變形的程度。本文利用鍛粗加工實驗所得到的實驗數據，做為驗證變分上界限法及傳統上界限法，在處理鍛粗加工問題的妥適性。

關鍵字

鍛粗 ； 上界限法 ； 變分 ； 摩擦

並列摘要

In this study, the materials of specimen were Al 6061 in the form of cylindrical and ring for a series of upsetting experiments. The plastic deformation behavior including the friction in the contact interface and measurement of bulging was observed the displacement by etching the nodes of the mesh on the surface of the specimen. The CCD and the X-Y platform were used for mseasuring the geometry coordinate of the nodes. Fluid velocity field during the deformation of material and bulging were observed by calculating the geometry coordinate of nodes of the mesh. The purpose of this study was to verify the appositeness of Variational Upper-Bound Method and Traditional Upper-Bound Method for the upsetting experiment by using the experimental data.

並列關鍵字

Upper-Bound Method ； Variational ； Upsetting ； friction

參考文獻

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