Functionally graded materials (FGMs) have a high potential in various engineering branches such as toolmaking, energetics, automotive, and aerospace engineering. In fabrication of FGM by laser direct deposition (LDD) it is crucial to deliver homogenous mixture of powders with selected ratios of component mass flow into the deposition spot. For this purpose, the existing LDD system had to be accordingly upgraded. To achieve this, the response time of disc powder feeder and the powder travel time were characterized as well as the composition of the delivered powder was validated. Based on the results, the existing control algorithm was modified. Various examples of thin wall FGM samples composed of stainless steel 316L and Inconel 718 were fabricated with the upgraded LDD system and evaluated. The results have confirmed that using the upgraded system, the predefined ratios and homogeneity of the powder mixture were achieved, assuring fabrication of FGMs with desired material composition properties.
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