Layerwise fabrication of refractory NiCrSiB composite with gradient grow of tungsten carbide additives by selective laser melting

Abstract

In the present paper, the selective laser melting process of multilayered 3D fabrication from metal matrix composites (MMC) based on nickel-chrome heat resistant alloy with WC ceramic reinforcing additive was implemented. The possibility of a laser powder bed fusion of functional grade (FG) 3D parts from these MMC for the account of increasing the alloying element concentration from 5% to 15%vol of the tungsten carbide in NiCrSiB self-fluxing alloy was shown. The optical and scanning electron microscopy, X-ray and EDX microanalysis, and microhardness measurements have been carried out to evaluate the structure formation features. We strongly recommend additional heating of the initially powdered mixture and/or substrate for temperature gradient reduction in the volume of the 3D part, homogenization of structure and decreasing residual stresses and propensity to delamination.