TiC/Ni3Al composite coating on steel was fabricated by self-propagating high temperature synthesis in Ti-C-3Ni-Al system with addition of a little of magnesium element.The effects of Mg on self-propagating process

composition and microstructure of thermal explosive product as well as microstructure of coating were analyzed by DSC（differential scanning calorimetry）

XRD（X-ray diffraction）

SEM（scanning electron microscope）and EDS（energy dispersive spectrum）

and micro-hardness and wear resistance at room temperature and high temperature were measured on the composite coating.It is found that addition of 2% Mg can accelerate the formation of TiC/Ni3Al coating and the bonding with the steel by decreasing initial reactive temperature and shortening reactive time as a result of effectively cleaning the surface of TiC particles.TiC particles with size of less than 1μm are uniformly distributed in Ni3Al phase in prepared coating

and metallurgical bonding between coating and steel can be observed

exhibiting gradient distribution in hardness from coating to steel matrix.The wear resistance of the composites is obviously superior to that of H13 steel.