抄録
This paper describes two methods of controlling residual stress in drawing process. The methods are residual stress controls by (1) "skin-pass" and (2) core-bar drawing that puts mandrel internally in tube. Finite element analyses are conducted in order to investigate the effect of reduction of area and tool geometries on the residual stresses. It is numerically clarified that the "skin-pass" is effective to suppress the residual stress for thick-wall tubes. On the other hand, "core-bar drawing" is effective for thin-wall tubes. These analytical results are verified by the experiments.
