Plasma Printing of Micro-Punch Assembly for Micro-Embossing of Aluminum Sheets

This paper concerned with micro-embossing of micro-cavities and micro-grooves into aluminum sheets by CNC-stamping with use of the arrayed DLC multi-punches. Both SKD11 and AISI420 steel die substrates were prepared and DLC-coated with the thickness of 10 to 15 μm. This DLC coating worked as a punch material. The two dimensional micro-patterns were printed onto this DLC film by maskless lithography. The unprinted DLC films were removed by the plasma oxidation to leave the three dimensional DLC-punch array on the steel substrate. This micro-pillared and micro-grooved DLC-punches were placed into the cassette die set for micro-embossing process by using the table-top CNC stamper. The micro-circular patterns transformed to the micro-pillars in the DLC punch by the plasma oxidation. Through the CNC-micro-embossing, this micro-texture further transferred to micro-cavities in the aluminum sheet. The dimensional accuracy of embossed micro-textures by stamping was measured by SEM and three dimensional profilometer with comparison to the tailored micro-pattern and the DLC-punch array configuration.