Speaker
Description
Laser-based Directed Energy Deposition (DED-LB) is an additive manufacturing method that has been heavily researched in recent years due to its potential in (1) producing complex parts, (2) prototyping metallic components, (3) cladding and surface treatment, and (4) manufacturing/repairing components in logistically weak locations. The focus of this study is on the microstructural evolution and properties of the laser cladding/repairing of Inconel 718 onto conventional Inconel 718 and a super duplex substrate. These alloys are widely used in marine environments due to their high strength and excellent corrosion resistance properties. Using DED-LB, bead-on-plates of Inconel 718 with different process parameters were deposited on the mentioned base materials to study the behavior of the bonds and strength. The investigation includes microstructure characterization, such as defects, nucleation, and evolution of grains during solidification, and segregation of elements at the interfaces between the deposited material and parent metals. Hardness tests are conducted to assess the defect levels, especially in cases where there is a lack of fusion under certain conditions. The hardness variation in different areas, i.e., the base metals, heat-affected zones, and fusion zone, was explained in terms of the microstructural observations. The result of this work is believed to help optimize the repair of precious components using the DED-LB process, which would otherwise be replaced with new components at a much higher cost.
