Thin wall deposition of IN625 using directed energy deposition

Abstract

Abstract Laser powder-blown directed energy deposition (DED) is widely used for small feature deposition ability and geometrical accuracy. The effects of process parameters, control, and toolpath strategies on geometry of the final product and mechanical properties have been investigated in many different parent geometries, however, deposition on an existing thin feature that has less width than the diameter of the laser spot size has yet to be addressed and is critical for various component repair applications. This study quantifies controllable factors contributing to optical characterization, geometry, characteristics of internal porosity, and microstructure of the deposit in the deposition processes of Inconel 625 by the laser powder-blown DED method. A full-factorial experimental plan was arranged with variations in laser power (175 W to 275 W) and mass flowrate (2 g/min to 20 g/min) on thin (0.5 mm) and thick (3.0 mm) substrate deposition. These results are useful for deriving an optimal workpiece quality through adjustment of controllable process parameters.