利用MARC探討非對稱壓延加工之彈塑性界面問題

陳永龍(Yung-lung Chen)

指導教授 ： 葉維磬

國立中央大學/工學院/機械工程研究所碩士在職專班/碩士(2014年)

摘要

摘要
所謂彈塑性界面，即板材壓延成形受輥輪擠壓產生塑性變形過程中彈性轉為塑性性質之交界面。就成形理論而言彈塑性界面即定義板材壓延成形塑性變形場區之邊界。
利用塑性成形理論探討塑性變形區之邊界，通常在忽略彈性變形影響下以低階多項式近似之，且此邊界於壓延實務過程中難以觀察得知。因此本論文藉由有限元素分析軟體MARC在考慮彈性變形之條件下，探討板材壓延成型在不同加工條件下的彈塑性界面變化，藉由分析板材元素上的塑性點，透過數學程式計算解析板材壓延過程中，材料內部所產生的彈塑性界面，使其了解板材壓延過程中所產生的彈塑性界面分佈情形，以期獲得較符合實際之塑性變形邊界，其中討論之加工參數有摩擦係數、壓縮率、周速比及輥徑比以及壓延後對板材曲率的影響。

關鍵字

彈塑性界面 ； 壓延加工

並列摘要

ABSTRACT
The elastic-plastic boundary is known as the interface that the plate materials switch form elastic to plastic by the compression of rolling by rolls.For the forming theories, the elastic-plastic boundary define the area of the plastic deformation that caused by the rolling of the plate materials.
The plastic deformation boundary discussed by theory of plastic forming usually ignores the effect of the elastic deformation and presented by the low order polynomials. It is also hard to be observed in practice of rolling. This research is subjected to the consideration of elastic deformation and focus on the change of the elastic-plastic boundary during the forming by the finite-element software, MSC. Marc. It is expected to get the practical model of the boundary of plastic deformation. Through mathematical formula to resolve the plate rolling process, Material Internally generated elastic-plastic boundary, Inform them about the plate rolling process generated distribution of elastic-plastic boundary, The following parameters are discussed in this thesis: the friction coefficient, the ratio of reduction, the ratio of velocity and the ratio of roll radius and the impact on the curvature of the plate after rolling.

參考文獻

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