In-situ formation, structural transformation and mechanical properties Cr-N coatings prepared by MPCVD

This study innovatively employed the microwave plasma chemical vapor deposition (MPCVD) technique to fabricate Cr-N coatings. The influence of preparation temperature on chemical composition, crystalline phase, morphology, and mechanical properties of the coatings were analyzed systematically. The increase of preparation temperature resulted in the structural transformation of the Cr-N coatings from the duplex of Cr2N/CrN to the single-phased Cr2N. The coatings with dense and flat surface were obtained at <= 800 degrees C; however, the decomposition of CrN to Cr2N and N2 led to the formation of pores at >= 850 degrees C and consequently an increase in friction coefficient and wear. The hardness and elastic modulus increased with increasing temperature because of the structural evolution of the Cr-N coating and phase transformation. 800 degrees C was the optimal preparation temperature as the coating exhibited a dense surface and possessed the best overall mechanical properties.

Automated summary

This study utilized the microwave plasma chemical vapor deposition technique to fabricate Cr-N coatings and systematically analyzed the influence of preparation temperature on the chemical composition, structure, and mechanical properties of the coatings. The results showed that higher preparation temperature led to a structural transformation of the coatings and an increase in hardness and elastic modulus. The optimal preparation temperature was found to be 800 degrees C, where the coating exhibited a dense surface and the best overall mechanical properties.