Process Design

The category of process design consists of research aimed at describing how the design is prepared for production. Liu and Rosen (2010) divide the process design

into three steps: Component orientation, slicing, and process variable optimization. Jin et al. (2017) added the, steps generation, path generation and post-processing steps to the definition of AM process design.

The choices made will have an effect on what the best design of the part (and probably the system) would look like, and iterations are therefore important. The exact steps to be taken in the process design step could be argued, but all steps from design to manufacturing are discussed in this review. In this review, the three categories of support structure, manufacturing settings, and AM simulation of manufacturing are chosen.

Creation End Evaluation of Support Structure

In the case of metal powder bed fusion, the AM support structure needs to be added in overhanging regions. The added support structure adds extra material to the manufacturing process, which adds production time, waste material, and postprocessing time for the removal of the structure. Overhanging regions and the addition of support structures also create worse surface structures compared to other areas. In order to minimize the support required for the construction of a part, there are three alternatives: Optimization of the form and location of the support structure, optimization of the build direction, and modification of the design to make the part self-supporting. The support structure is directly linked to the choice of construction direction during development. Leutenecker-Twesiek et al. (2016) underline the importance of an early decision on part orientation for a product manufactured using AM. The purpose is to allow the implementation of design rules and guidelines that enable the development of self-supporting components and reduce the amount of support structure. Automated methods for choosing the best construction path to minimize the amount of support structure are described in (Strano et al., 2013a, 2013b) and (Zwier and Wits, 2016). Das et al. have merged various output goals for multi-objective optimization. In one analysis, the amount of support structure is minimized and the error of the part produced due to the effect of the stairs is minimized.

The amount of support structure and build-up time is minimized in another study. The creation of a support structure could be carried out in different ways and is often based on some mathematical algorithm that analyzes geometry in combination with the construction direction. Challenges in the design of a support structure include identifying areas that need support, reducing the amount of support, providing support with adequate mechanical properties (structural strength and heat dissipation), and providing support that is easy to remove.

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