Operational factors in copper wiredrawing such as back tension, drawing direction and die-misalignment against wire properties have been investigated by the experiment and Finite Element Analysis. Although back-tension drawing has some advantages, such as long die life or homogeneous forming, when back tension is excessively exerted, the voids or internal fractures occur easily and the mechanical properties of the drawn wire deteriorate. By using a winding system with spool in some continuous drawing machines, the drawing direction changes. The subsequent change in the drawing direction seems to have no effect on the onset of internal defects, except that it takes a shape similar to that of the figure W. When the wire and die axis are misaligned, the internal fracture is caused more readily.
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