Until now the characterisation of transfer films in terms of their mechanical properties has been hampered by their non-homogeneous distribution across a tested surface, their small size, low thickness and the difficulty in accurately positioning a test probe such that the film properties can be measured independently from those of the substrate.
Some previous work has already shown the net advantages of nanoindentation as a unique tool for the characterisation of tribological transfer films created with a steel/polymer material pair in both ambient air and cryogenic environments. However, when two bodies consisting of hard and soft materials respectively are subjected to such testing, the apparition of a buy PET transfer film, or third body, which can be a composite mixture of the two, is often observed.
Distinct variations in hardness between the transfer films and their contacting bodies were observed and correlated to the wear behaviour and testing environment. In this study, the mechanical properties of transfer film wholesale created between material pairs of significant industrial importance were investigated, namely hard coatings (TiN, TiCN, TiAlN, CrN) for tool applications and bulk ceramics (Al2O3, WC).