SURFACE CHARACTERISTICS AND WEAR RESISTANCE OF AlCrTiSiN COATINGS AT HIGH TEMPERATURES

AlCrTiSiN coatings were deposited on YT14 cemented carbide using cathodic arc ion plating (CAIP) method. The surface and cross-section morphologies, chemical composition, phases, surface roughness, and binding energies of chemical elements of obtained coatings were analyzed using a field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), X-ray diffractometer (XRD), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), respectively, and its mechanical properties were characterized using a scratch tester and nanoindentation tester. The friction-wear behaviors of AlCrTiSiN coatings at 700∘C, 800∘C and 900∘C were investigated using a high temperature wear test, the distributions of chemical elements on the worn tracks were analyzed using a plane scan analysis of EDS, and the high temperature wear mechanisms were also discussed. The results show that the chemical elements are uniformly distributed on the AlCrTiSiN coating with the surface roughness of 105nm, which is composed of faced centered cubic (FCC)–(Cr, Al)N, body-centered cubic (HCP)–AlN and Si3N4 amorphous phases. The interfacial bonding strength, microhardness and elastic modulus of AlCrTiSiN coating is 26.15N, 25.789GPa, and 251.364GPa, respectively. The average coefficient of friction (COF) of AlCrTiSiN coatings at 600∘C, 700∘C and 800∘C is 1.06, 0.73, and 0.97, respectively, of which friction performance is the best at 700∘C. The wear mechanism of AlCrTiSiN coating at 600∘C, 700∘C and 800∘C is adhesive wear + fatigue wear, abrasive wear + oxidation reaction, and adhesive wear + fatigue wear, respectively.