Syntheses and Properties of Quaternary Cr-Ti-B-N Coatings by a High Power Impulse Magnetron Sputtering Technique

Abstract

Cr-Ti-B-N coatings were synthesized by a hybrid coating system combining high power impulse magnetron sputtering (HIPIMS) and DC pulse magnetron sputtering from a TiB2 and a Cr target in argon-nitrogen environment,respectively. By changing the power applied on the Cr and TiB2 cathodes, the Cr-Ti-B-N coatings with various Ti/Cr ratio and B content were deposited. The phase structure, microstructure and chemical compositions of the Cr-Ti-B-N coatings were studied by X-ray diffraction (XRD), transmission scanning electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). With increase of Cr element in the coatings, the nanocomposite microstructure consisting of nano-sized (Cr, Ti) N crystallites and amorphous BN phase were obtained in the coatings. The microhardness of the Cr-Ti-B-N coatings exhibited a peak value of ~41 GPa for the CrTi0.1B0.4N1.3, and then decreased with further increase of Cr content in the coatings,and all the coatings exhibited low friction coefficient. The oxidation and corrosion behavior of th