Preparation and Properties of MAX Phase High-Temperature Antioxidant Coatings on C/C Composite Surfaces by Ultra-High Speed Laser Cladding

Abstract

Prefabricated MAX (Ti3SiC2, Ti3AlC2) phase coating materials with coefficient of thermal expansion Si and SiC as transition layers and excellent high-temperature antioxidant properties were used for ultra-high-speed laser melting on the surface of carbon/carbon composites, so that the produced coatings have good interfacial bonding and high-temperature antioxidant properties. In this study, we characterised and analysed the microscopic morphology and composition of the sample coatings using X-ray diffraction and scanning electron microscopy, investigated their interfacial bonding properties by scratch tests and studied the high temperature oxidation resistance of the samples at 1773 K for 1 h. The results show that the bonding strength between the coating and the substrate is good, the surface is flat without flaking, the coating thickness can be controlled below 60 μm, the microstructure is dense, and there is no obvious deformation or failure of the substrate, and the dense coating formed by laser melting has strong oxidation resistance, so that the substrate carbon/carbon composite is well protected at high temperature.