Model-based design of areal material measures with component surfaces

Abstract

The calibration and verification of areal surface topography measuring instruments is usually performed with artificial geometries that do not correspond to a practical measuring task like gratings or step height artefacts (ISO 25178-70:2014). While these processes have a sufficient process capability to meet the requirements of many industrial measurement applications, there are more and more applications that require small tolerances, which results in the necessity of a performance verification that is more closely related to the later performed measuring task. With a model-based design approach it is possible to design material measures based on component surfaces for an application-oriented performance verification. The initial point is a measured dataset, which is evaluated and virtually transformed in a way that on the one hand the target properties are met, but on the other hand also the functional properties of the surface that are relevant for the specific application are preserved. Based on the subsequent application of virtual manufacturing and measuring processes, also impacts from these processes can be considered in the design of the verification sample. In this study, we extend the basic approach that has been developed for the design of profile material measures e.g. with the manufacturing principle of ultra-precision turning (Seewig, Eifler, Schneider, Aurich Proc. CIRP 45 (2016), 259-262; Eifler, Schneider, Seewig, Kirsch, Aurich Eng. Sci. Technol. 4 (2016) 1993-2001. Seewig, Eifler, Schneider, Kirsch, Aurich Surf. Topog.: Met. Prop. 4 (2016) 024010. Eifler (2016)). to areal material measures and a corresponding manufacturing principle of micro-milling. With the model-based design approach, component surfaces are used to determine two different material measures that feature defined values of the surface texture parameters Sa, Sq, Sk, Svk, Spk as a case study. It will be shown that the areal surface texture parameters can be mapped to the designed material measures that enable a practical performance verification.