Tribological properties of ternary BCN films with controlled composition and bonding structure

In this work we study the mechanical and tribological properties (hardness, elastic modulus, friction and wear) of BCN coatings with controlled composition and structure. The influence of the carbon content in films with BCxN stoichiometry is discussed in connection with the bonding structure, and compared with the mechanical and tribological properties of reference compounds. Since ternary BCN compounds can exhibit a variety of compositions and bonding structures, the knowledge of these parameters is a pre-requisite to study any physical property of BCN coatings. Boron carbonitride (BCN) films were deposited at different temperatures using simultaneous evaporation from separated boron and carbon sources, assisted by different mixtures of Nitrogen and Argon ions from a Kauffman ion gun. In this way, we obtained films with selected composition, as verified with Energy Dispersive X-ray (EDX) spectroscopy, X-ray Absorption Near Edge Spectroscopy (XANES) and Elastic Recoil Detection Analysis (ERDA). The bonding structure of the coatings was determined by combining XANES with vibrational spectroscopies (infrared and Raman). Finally, the mechanical and tribogical characterization was performed with nanoindentation and pin-on-disk techniques, respectively.