Laser Cladding Functionally Graded Composition of Molybdenum Disilicide and Co-Based Alloy

An approach for fabricating functionally graded specimens of Co-based alloy and molybdenum disilicide (MoSi2) compositions via Selective Laser Cladding (SLD) is presented. The focus aimed at using the functionally graded material (FGM) concept to gradually grade powdered compositions of MoSi2 within a base material of Co-based alloy. A high power CO2 laser was used to process the material compositions to a high density with gradual but discrete changes between layered compositions. The graded specimens initially consisted of 100% Co-based alloy with subsequent layers containing increased volume compositions of MoSi2 (0-80wt.%). Specimens were examined for porosity, phase composition and microstructure. It was found that crack sensitivity of layer can be reduced by adding Co-based alloy into the pure MoSi2 powder.