Microstructure, wear and friction coefficient of cr-based magnetron sputtered layers. CrN films were deposited on stainless steel and silicon substrates via magnetron reactive sputtering under a systematic variation of the substrate bias voltage. The influence of the substrate bias voltage on the structural and tribological properties of the films was investigated. The results indicated that increasing the negative bias voltage have many influence on the characteristic of the coatings: concerning their microstructure, we observed that the grain size increased, while their coefficient of friction is influenced by the bias voltage like the wear rate.