Abstract
Additive manufacturing based on robotic welding is used for the manufacturing of metal parts by applying an arc as a heat source and wire as feedstock. The process is known as Wire Arc Additive Manufacturing (WAAM). However, the current WAAM process has a limitation in fabricating block structure components with high geometry accuracy and consistent welding due to the process complexity and lack of appropriate process planning method. Furthermore, common defects such as voids, gaps and collapse decrease the mechanical properties of the final product. This thesis presents a novel process planning method based on a Mixed Heat Input(MHI) strategy to minimise voids and collapse defects that occur in fabricating large block structure components while maintaining a high manufacturing efficiency. By dividing each layer into a boundary layer and multiple inner layers, the MHI method applies various heat input conditions at different positions of the layer allowing the construction