Direct Three-Dimensional Layer Metal Deposition

Multi-axis slicing for solid freeform fabrication manufacturing processes can yield nonuniform thickness layers or three-dimensional (3D) layers. The traditional parallel layer construction approach to building such layers leads to the so-called staircase effect, which requires machining or other postprocessing to form the desired shape. This paper presents a direct 3D layer deposition approach that uses an empirical model to predict the layer thickness. The toolpath between layers is not parallel; instead, it follows the final shape of the designed geometry and the distance between the toolpath in the adjacent layers varies at different locations. Directly depositing 3D layers not only eliminates the staircase effect but also improves manufacturing efficiency by shortening the deposition and machining times. Simulation and experimental studies are conducted that demonstrate these advantages. Thus, the 3D deposition method is a beneficial addition to the traditional parallel deposition method.