PVD nitrides to be used for increased life time of tools and components

Abstract

For mechanically dominated load profiles, nitrides are preferred, while oxides offer better protection against high-temperature corrosion. Combined mechanical and thermal loads therefore call for nitrides with excellent temperature and oxidation resistance. How to develop such nitrides with excellent strength and toughness combined with exceptional thermal stability is the focus of this talk. Using transition metal nitride coatings, we will discuss important guidelines for material development to improve strength, fracture toughness, and stability. In particular, the stability (emphasis on phase stability to composition and temperature, but also to oxidation) of nitrides is a highly interesting task. We will discuss various model systems to explore the possibilities of alloy and structural developments. The concept of high entropy is also very beneficial for hard ceramic thin films. We will see that, for example, (Hf,Ta,Ti,V,Zr)N and (Al,Cr,Nb,Ta,Ti)N easily outperform their commonly used binary or ternary constituents in terms of thermal stability and thermomechanical properties. In addition, all of the highly entropic ceramic sublattice thin films studied were relatively insensitive to variations in deposition parameters – which is good because their properties are at a high level. The individual concepts allow the materials to be designed to meet the ever-growing demand for further coatings tailored to specific applications.