Latest findings on the fracture toughness of Ti-Si-N thin films

Tests in the Christian-Doppler-Laboratory at the Vienna University of Technology investigated the fracture toughness of Ti-Si-N coatings, produced using special Ti-TiSi2 targets from Plansee Composite Materials GmbH.

Nanocomposite thin films are a special kind of hard coating with attractive mechanical properties such as high hardness and strength values. The self-organizing nanostructures are typically made up of a nanocrystalline transition metal nitride, embedded in an amorphous, covalent nitride phase. One of the systems most frequently investigated in this context is titanium silicon nitride (Ti-Si-N). Although the considerable hardness of these types of coatings has already been discussed extensively in numerous studies, little is known about their fracture toughness, i.e. the resistance of the material against the propagation of existing cracks. Now, Plansee - in cooperation with Oerlikon Surface Solutions AG and the Institute of Materials Science and Technology, at the Vienna University of Technology - has established quantitative fracture toughness values for Ti-Si-N coatings on the basis of micromechanical trials under a scanning electron microscope. The authors demonstrate the dependence of fracture toughness on the phase composition and microstructure of Ti-Si-N coatings produced using special Ti-TiSi2 targets from Plansee Composite Materials GmbH. Plansee manufactures powder-metallurgical Ti-Si targets for a wide range of the compounds for which there is a demand. It is thus possible to control the properties of the coatings deposited in the PVD process by an appropriate silicon content in the targets (up to 30 at % Si) and hence also in the coatings themselves.

The authors M.Bartosik, R.Hahn, Z.L.Zhang, I.Ivanov, M.Arndt, P.Polcik and P.H.Mayrhofer have released details of the research findings in a paper entitled „Fracture toughness of Ti-Si-N thin films” in the International Journal of Refractory Metals and Hard Materials.

You can download the complete paper HERE.

Would you like more information about sputtering targets from Plansee? Visit our website Plansee Composite Materials or email us at plansee-cm(at)plansee.com.