Effect of Punching Conditions on the Stretch Flange Formability of Cold rolled Steels for Deep Drawing

편칭조건이 가공용 냉연강판의 신장플랜지 성형성에 미치는 영향

In order to investigate the effect of punching condition on the stretch flange formability of sheet for deep drawing hole expansion tests at various edge condition were done. Edge conditions were changed by altering tool clearances artifical defects grinding and deburring. For a determination of optimum edge condition of side panel of automobile punched section analysis and forming results were studied and the laboratory test results were used. In case of considered side panel tool clearance should be less than 15% and punched edge should be uniform without defects for safe forming