Microstructure and mechanical properties of as-deposited and annealed TiB2/BN superlattice coatings

► TiB2/BN multilayers have potential as protective coating in dry machining. ► Annealing is found to be beneficial for thermal stability. ► The highest hardness of 39.34 GPa appears at tTiB2:tBN = 13:1. ► Good thermal stability of the properties of annealed layers is observed. ► Thermally stable TiBxNy phases contributes to stable layer structure and properties.