Surface modification of forming tools for aluminum sheet metal forming

Abstract

It is known that surface patterns and coating systems can affect the flow behavior of forming tools. In this context, we report about the surface modification of forming tool steels for aluminum sheet metal forming process. Microstructures with variable spatial periods and depths are fabricated on tool steel samples using the direct laser interference patterning method. A picosecond-pulsed in-frared laser source with a two-beam interference setup is applied for producing line-like structures. In addition, a diamond like carbon (DLC) coating system is deposited on the structured surfaces. To improve the adhesion tendency of the DLC coating, also different plasma nitriding parameters are examined. According to the results, a broad spectrum of different coating-structure combinations can be efficiently processed, which can optimize the tribological properties of the forming tool for aluminum forming applications.