Laser deposited welding of functional gradient materials with powder feeding

Laser deposited welding of stainless steel and iron-based alloy was carried out with synchronized powder feeding method.The microstructure,properties and composition of the deposited layer were thoroughly analyzed and tested by means of microstructural observation,SEM scanning,tensile strength testing,wearing and EDAX analysis.Different process and property requirements at different deposited position can be satisfied with functionally gradient combination of different welding materials.The deposited welding layer presents a metallurgical bonding with the substrate,and the dilution is quite small.The microstructure obtained is fine,compact,and free of cracking and porosity.The tensile strength of the samples at the bottom of the deposited layers reaches 752.4 MPa,and the elongation 41.05%.The wearing resistance of the surface layer has greatly surpassed that of the substrate.The optimized matching of materials and properties can be realized by laser deposited welding with powder feeding,which provides an effective way for the forming and functional gradient repairing of metal components.