Nd-YAG Laser Sculpture of WC Punches for Micro-Sheet Forming

A Q-switched Nd-YAG laser was used to sculpt a WC micro-punch in a sintered preform. A cylindrical punch was obtained with a nominal diameter of 400 μm and 80 μm in height. Laser machined surface was characterized both qualitatively and quantitatively by means of scanning surface topography instrument. A 20 μm thick aluminum sheet was micro-punched using a testing machine as a drive and a gasket material for support. The gasket followed the micro-punched disk during all the shearing process, collapsing under the punching load. This simple forming process was defined to reduce the micro-part distortion and to avoid the fabrication of a micro-die. Finally, optical microscopy showed that the punched part had a flat surface in the centre and some anomalies at the edges where the punch melted zones were reproduced.