Friction in Sheet Metal Forming - A Comparison Between Milled and Manually Polished Die Surfaces

Paper i proceeding, 2010

The evolvement of product requirements in the automotive industry, e.g. reduced weight, means that the use of advanced high strength steels (HSS, EHSS,UHSS) in automotive applications is continuously increasing. The introduction of high strength steels in production implies increased tool wear and calls for functional tool surfaces that are durable in these severe tribological conditions. In this study the influence of tool surface topography on friction has been investigated. The frictional response was studied in a Bending Under Tension test. The results did show that a low frictional response was generated by low slope of roughness profiles combined with a strong anisotropy applied perpendicularly to the sliding direction. An improved machining strategy has a high potential to significantly reduce the need for manually polished surfaces.