Measurement of Skid Line Formation and Formation Mechanism of Automotive Outer Panel

Abstract Appearance of an automobile is one the appealing points to customers. Character ridgelines in outer panels such as hood and door play important role make automobiles attractive, a sharp character ridgeline which has ridge small curvature radius much more preferred blunt ridgeline. However, skid line, kind appearance defect, apt generate along press forming Although it well-known that lines are caused by inhomogeneous tension, mechanism line generation was not yet fully understood. In this study, defect quantitatively evaluated draw experiment using newly devised die can measure panel shape at any time during forming. The formation clarified experimental results. results measurement suggest formed on punch should move flat area punch. A wavy be generated there immediately before flattened bottom dead center die. Then grow through springback.