Process-Driven Manufacturability Constraints in Design for Wire Arc Additive Manufacturing

Abstract

Abstract Wire arc additive manufacturing (WAAM) has emerged as a useful option for large-scale metal additive manufacturing. It has gained widespread use in the aerospace industry and other applications that require large and complex custom parts. The process is a combination of a precise control system and a welding process, typically GTAW or MIG welding. It is a member of the directed energy deposition (DED) family of AM processes. Compared with many metal AM processes, it is relatively simple and cost-effective but almost always requires a significant amount of postprocessing before parts can be used. The AM-based nature of the process and its unique mechanics make designing parts for it challenging, particularly in cases where the designer does not have much technical experience with the process. Therefore, a way to obtain the process constraints in a way that is useful in design without over-restricting the design space is needed. This project explores a technique for mapping realistic manufacturability constraints from the process directly to the designed parts, which is useful for several different types of design problems. During this work, important manufacturability constraints were identified by directly mapping the process mechanics. The results of this work will be very useful in formulating design problems in which the final part will be fabricated using WAAM. An illustrative case study was developed to demonstrate the method.