Fine-Blanking Punch Edge Control by Chamfering and Plasma-Nitriding under Excessive Load Situation

A fine blanking (FB) has grown up as a manufacturing means to fabricate the precise automotive parts from the thick sheet metals. During this net-shaping process, each part product had fully burnished surfaces through a single stroke. The punch for this FB, were highly loaded enough to distort the punch edge and to deteriorate the cost competitiveness and sustainability. A chamfered SKH51 tool steel punch was designed by controlling the chamfer widths and angles. A massively nitrogen supersaturated SKH51 punch was also prepared to investigate its effect on the suppression of punch edge distortion. AISI304 stainless steel work was used to describe the variation of punch distortion and blank qualities with increasing the number of strokes.