Functionally graded 3D structures produced by laser cladding

In this study, three-dimensional metallic structures of functionally graded materials (FGMs) were produced using the one step laser cladding technique. AISI 316L with particle size between 63 and 125 µm and a cobalt based super-alloy with 90 µm of average particle size, were used as precursor materials. A Yb:YAG continuous wave fiber laser (λ=1075 nm) was chosen as the energy source of the laser cladding process. By means of a new powder feeder system specifically developed for this work, the precursor materials were mixed and homogenized in the desired percentage. Moreover, the new powder feeder allows the live modification (during the processing time) of the material concentrations, in order to obtain three-dimensional structures with a smooth gradient of the precursor material. The study was completed with the analysis of the microstructure, chemical composition and micro-hardness of the obtained samples.