Effect of MoS2 content on friction and wear properties of Mo and S co-doped CrN coatings at 25-600 °C

With increasingly harsh working environments for mechanical systems and the rapid development of various high-tech industries, requirements for the stable operation of mechanical systems are increasing in a wide temperature range. Mo and S co-doped CrN coatings with different MoS2 contents were prepared via unbalanced magnetron sputtering to provide better friction properties to the coatings at high temperatures. Scanning electron microscopy and nanoindentation were adopted to analyze the microstructure and mechanical performance. The mechanical performance of the coatings was enhanced by increasing the MoS2 content, however, excessive MoS2 reduced the mechanical properties of the coatings. Besides, the adhesion of the coatings first increased and then decreased rapidly with the increase of the MoS2 content. In addition, the residual stress of the coating first decreased and then increased upon increasing the MoS2 content. The high-temperature tribological behavior of the coatings was measured from room temperature (25 degrees C) to 600 degrees C. The CrN/MoS2-0.6A coating was found to exhibit low friction and wear coefficient at room temperature and relatively good comprehensive properties at high temperature. This study provides a feasible design for engineering applications and lays the foundations for the preparation of coatings with superior high-temperature friction properties.

Automated summary

This study prepared Mo and S co-doped CrN coatings with different MoS2 contents to provide better friction properties at high temperatures. Increasing the MoS2 content enhanced the mechanical performance of the coatings, but excessive MoS2 reduced their properties. The adhesion and residual stress of the coatings changed with the increase of MoS2 content.