異形複合包芯材是指由兩種或兩種以上不同材料所組成具有矩形、長方形、六角形或其他不規則之非軸對稱斷面形狀的纖維型複合材。這一類異形複合包芯材在工業上廣泛的應用於電極導體及化學工程設備方面，近來極受注目的超導線材在其製造的過程中為了增加超導芯線的疊積密度，也將超導線作成六角形斷面之棒 ( 線 ) ，被覆於純銅等之常導體內部。一般異形材多利用擠製加工使圓形棒狀素材經由模具的擠壓作用使材料產生塑性變形製成具有各種異形斷面的型材。在擠製過程中，由於構成複合材的材料具有不同的機械性質，並且因被覆材與芯材的非同心配置（多芯的場合）及模具在斷面形狀何上的變化，將使材料的變形流動模式有驅向於不均勻變形的傾向，因而導致芯材或被覆材的斷裂及成品未能完全充滿模具等缺陷，以致得到不良的擠製產品。目前有關異形複合包芯材擠製的研究報告尚十分缺乏，本研究的目的在於以上界法探討在不同的加工條件組合下芯材及被覆材的變形行為，判斷健全擠製的加工範圍，並求出不同材料組合之下的最適加工條件及加工荷重等並以實驗檢討解析結果的可靠度。
Composited Clad rods with square, rectangular, hexagonal or other non-axisymmetric cross-sectional areas are commercially important because of their intensive application in the industry as electrodes, conductors and chemical devices. Even the sensational superconductor, in order to make @ a useful wire, we need to process the usually round bar to hex- agonal one. The hexagonal superconductor bars can packed more densely inside the high parity copper tube, thus increase its critical current range. Non-axisymmetric bars or wires are most often made by extrusion. During the process, billet are deformed by the die surfaces to become various shapes. Because composited Clad rods are composed of different materials with different mechanical properties during the extrusion process, there is a tendency for non-uniform deformation of cores and sleeve. Besides, non-axisymmetric arrangement of the core and sleeve often induces fractures and sometimes non till-up the die corner.
Reports about the above mentioned non-axisymmetric composited clad rods are vary scarce. This project is intended to study the deformation patterns of core and sleeve under various extrusion conditions, find out the required load, the conditions that different material combination can safely processed. The reliability of the analysis will be checked by the experiment.