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H. Riedl, J. Zalesak, M. Sobiech, P. Polcik, D. Holec, P.H. Mayrhofer:
"Ab initio studies on the Adsorption and Adhesive Transfer of Al and Fe to Nitride Coating Materials";
Talk: 2nd Austrian-Indian-Symposium on Materials Science and Tribology, Wiener Neustadt; 2014-05-26 - 2014-05-28; in: "Book of Abstracts", (2014).

Computational studies such as finite element methods (FEM), molecular dynamics or ab initio calculations are integral parts of state of the art materials design. While FEM is commonly used to investigate flow behavior, strain and temperature profiles in various machining processes, this work focuses on utilization of ab initio calculations for an atomistic insight into material transfer phenomena during metal machining.
Material transfer from the workpiece onto the coated tool surface is generally considered as troublesome in machining operations, as the tool and/or work piece surface can severely lack quality over operational time. However, the material adhesion results from a complex interaction of machining conditions, workpiece and coating material. As one crucial parameter we focussed on the tribological contact between nitride coating and work piece material and employed ab initio calculations to estimate the chemical driving force for the formation of transfer material build-up at the coated tool surface.
We thereby investigated the adsorption energies of iron and aluminum with respect to different coating systems (TiN, AlN, TiAlN, TiSiN, CrN, and CrSiN) and were thus able to describe the energetic interplay between workpiece and coating material. The obtained results propose that especially Si containing coatings clearly decrease the adsorption energy for Al, but have less effect on Fe.
The present study introduces a methodology to thoroughly understand tribosystems at the atomic level, which further enables for an efficient coating material screening and selection as an alternative to cost and time consuming experiments.