Shape formation after laser hardening for high-precision micro-cutting edge

Micro-cutting edges are often used for the die cutting of functional films and paper containers. A hardening process is needed here because the ridgelines of micro-cutting edges require not only wear resistance but also sharpness and shape accuracy. A method of laser hardening after machining for the micro-cutting edge fabrication has previously been developed. This process uses laser hardening after shape fabrication of a micro-cutting edge in a pre-hardened steel workpiece. However, since the edge's heat capacity is limited, edge melting can occur because of overheating during laser irradiation, and a method to overcome this issue is thus needed. Thus, we propose a novel method of micro-cutting edge shape formation after laser hardening with demonstrable effects for micro-cutting edges with a straight ridgeline. Various trials were conducted to evaluate the applicability of this method for curve-shaped micro-cutting edges. As a result, useful knowledge for the creation of high-precision micro-cutting edges using the proposed method was obtained.