Effect of spreading of the melt pool on the deposition characteristics in laser directed energy deposition

Abstract

Laser direct energy deposition (DED) is an innovative additive manufacturing technology with tremendous potential for remanufacturing and restoration of dies, molds, and components for aerospace. Accurate prediction of the deposition geometry is important to control the repair quality. In laser DED, the powder particles are fused onto the melt pool formed on the substrate surface. To estimate the deposition geometry estimating the spreading and solidification of molten pool is of utmost importance. Therefore, a computation fluid dynamics (CFD) model has been developed to estimate the melt pool size on the substrate and the spreading of the melt pool over the substrate before solidification. The model can be also used to estimate the catchment efficiency and deposition geometry. The experimental observations of solidified deposition geometry on a substrate corroborate the proposed model. The CFD model is utilized to develop data-driven models correlating the process parameters with the deposition geometry. This study, observes that larger the width of the deposition, important is the inclusion of the spreading of melt pool in the estimation of the deposition geometry.