Characterization and friction–wear behaviors of cathodic arc ion plated AlCrTiN coating on HVOF sprayed WC–12Co coating at elevated temperatures

Abstract

An AlCrTiN coating was deposited on high velocity oxygen fuel (HVOF) sprayed WC–12Co coating using a cathodic arc ion plating (CAIP). The surface and cross–section morphologies, chemical elements, and phases of obtained AlCrTiN coating were analyzed using a scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and x–ray diffractometry (XRD), respectively, and its surface roughness and chemical valences were analyzed using a atomic force microscopy (AFM) and x–ray photoelectron spectroscopy (XPS), respectively. The mechanical properties such as nanohardness and modulus of elasticity and bonding strength of AlCrTiN coating was measured using nanoindentation and scratch tests, respectively. The friction–wear behaviors were evaluated at 600, 700 and 800 °C using a high temperature pin–on–disc tribometer. The results show that the AlCrTiN coating presents a (111) preferred orientation, its nanohardness and modulus of elasticity is 22.09 and 347.52 GPa, respectively, and its bonding strength is 32.9 N. The average coefficient of friction (COF) at 600, 700 and 800 °C is 1.40, 1.24, and 0.76, respectively, and the corresponding wear rate is 5.13 × 10–6, 5.71 × 10–6 and 14.16 × 10–6 mm3 · N–1 · s–1, exhibiting the reducing friction and decreasing wear at high temperatures, the wear mechanism is primary abrasive wear and oxidation wear.