Ab initio studies on the adsorption and implantation of Al and Fe to nitride materials

Abstract

The formation of transfer material products on coated cutting and forming tools is a major failure mechanism leading to various sorts of wear. To describe the atomistic processes behind the formation of transfer materials, we use ab initio to study the adsorption energy as well as the implantation barrier of Al and Fe atoms for (001)-oriented surfaces of TiN, Ti0.50Al0.50N, Ti0.90Si0.10N, CrN, and Cr0.90Si0.10N. The interactions between additional atoms and nitride-surfaces are described for pure adhesion, considering no additional stresses, and for the implantation barrier. The latter, we simplified to the stress required to implant Al and Fe into sub-surface regions of the nitride material. The adsorption energies exhibit pronounced extrema at high-symmetry positions and are generally highest at nitrogen sites. Here, the binary nitrides are comparable to their ternary counterparts and the average adhesive energy is higher (more negative) on CrN than TiN based systems. Contrary, the implantation barrier for Al and Fe atoms is higher for the ternary systems Ti0.50Al0.50N, Ti0.90Si0.10N, and Cr0.90Si0.10N than for their binary counterparts TiN and CrN. Based on our results, we can conclude that TiN based systems outperform CrN based systems with respect to pure adhesion, while the Si-containing ternaries exhibit higher implantation barriers for Al and Fe atoms. The data obtained are important to understand the atomistic interaction of metal atoms with nitride-based materials, which is valid not just for machining operations but also for any combination such as interfaces between coatings and substrates or multilayer and phase arrangements themselves.