Micro-scratch tests as a method for determining the wear resistance of high-speed blanked surfaces

Abstract

Compared to conventional cutting processes such as normal or fine blanking, high-speed blanking (HSB) is an economically and ecologically relevant alternative to produce sheet metal parts. Depending on the material and the process parameters, the microstructure is significantly affected, and adiabatic shear bands (ASB) can form due to the localisation of the induced deformation. The resulting HSB surfaces are characterised by high hardness, small rollover depth and width, low roughness, and almost no burr. Therefore, HSB is a promising strategy for producing blanked surfaces, which can be used directly as functional surfaces without further post-processing steps. Besides the surface quality, properties like the wear resistance are relevant for technical applications. To enable the production of functional surfaces, which meet the requirements for the application, the understanding of the relationships between the blanking process parameters, the resulting microstructure, and the surface properties is essential. As standardised macroscopic wear testing methods are often not applicable to the geometrically complex shear-cut surfaces, in this study a first approach was taken utilising the micro-scratch test method for determining the scratch resistance directly measured on the blanked surface.