High-quality wires, which are used for components such as valve springs of automobiles, are fabricated by rolling and drawing. Even a minute flaw on the surface of the wire leads to a significant decrease in fatigue strength. Under such circumstances, high-quality wires are fabricated, at many wire manufacturing factories, by rolling and drawing after removing surface flaws on the raw material. However, the flaw removal process is carried out relying on the experience of onsite workers; many of the mechanisms underlying flaw removal have not been clarified. In this study, billet and wire that have traces formed during flaw removal were subjected to rolling and drawing to investigate the behavior of deformation and the recovery of the flaw-removal traces. When flaw-removal traces exist on a billet surface that comes into contact with the roll used in rolling, the traces are removed without difficulty. However, when the flaw-removal traces exist on a surface that does not come into contact with the roll, the traces tend to become wrinkles due to compression from the upper and lower directions. Two cases of drawing, i.e., when only the flaw part is removed and when the flaw part and the surrounding area are removed, were examined. The results of three-dimensional finite-element analysis (FEA) indicate that the removal of the flaw and the surrounding area results in a better outcome in terms of uniform recovery behaviour than the removal of the flaw alone.
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