Additive Manufacturing of Complex Shapes Through Weld-Deposition and Feature Based Slicing

Abstract

Fabricating fully dense and functional metallic components is one of the important challenges in Additive Manufacturing (AM). Additive Manufacturing is a technology in which functional components can be fabricated rapidly and efficiently from their CAD models. It is also referred as Layered Manufacturing (LM) as the object is created by slicing the CAD model into layers and realizing each layer at a time. These layers are thin and stacked or glued together to get the physical shape of the CAD model. However, realizing overhanging features is a difficult task due to deficiency of support mechanism for metals. A separate support structure has to be deposited to build overhanging structures. Although, use of a distinct support material is quite common in non-metallic AM processes, such as Fused Deposition Modelling (FDM), and the same for metals is not yet available. The various techniques in AM process for fabricating metal parts can be mainly classified as laser based, electron beam based and arc based processes. While some Additive Manufacturing processes like Selective Laser Sintering (SLS) employ easily-breakable-scaffolds made of same material to realize the overhanging features, the same approach cannot be extended to deposition processes like laser or arc based direct energy deposition processes.