In-situ synthesis of MoSi₂/SiC composite coating by laser cladding Available to Purchase

In order to improve resistance to high temperature and wear resistance of pure aluminum, the laser cladding experiments were conducted on a 3kW continuous wave CO₂ laser to produce in-situ synthesized MoSi₂/SiC composite coatings on pure aluminum. The laser consolidified microstructure and phase evolution were investigated using scanning electron micrograph and x-ray diffraction. The in-situ formation of MoSi₂ /SiC was conducted by adding a mixture of Mo, Si and C precursor powder layer followed by melting the layer and substrate under a laser beam. The experimental results showed that these compound, MoSi₂ and SiC can be formed from three distinct powders of Mo, Si and C on Al alloy, provided that supplied energy was sufficient to start the reaction between the initial products, a good metallurgical bond between coating and the substrate can be achieved. The microstructures of the coating were composed of MoSi₂, Mo₅Si₃ and SiC phases. The microhardness of coating was about twelve times that of the aluminum substrate, the maximum value reached HV_0.21200.