Deformation of Material in Punching of Slanted Fine Hole in SUS304 Sheets with Fine-Grained Microstructure

Abstract

It is necessary to understand behaviors of the material in worked sheet to reduce troubles of punch fracturing in the punching of slanted fine holes in austenitic stainless-steel SUS304 sheets. The behavior of the material is estimated as the follows by the map of Vickers hardness in the cross-section of worked sheet. The material flow changes the complexity of what as a result of the influence of work hardening or transformation to strain-induced martensite. Then, the direction and magnitude of the pressure applied to the punch also change such inn a complex manner. However, the worked material almost flows into the die hole. Then, the punch is carried into the hole by this material flow.