Temperature field simulation by finite element method on wire arc additive manufacturing of mild steel

• Main Author: Sun, Xin
• Other Authors: Zhou Wei
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2023
• Subjects: Engineering::Mechanical engineering
• Online Access: https://hdl.handle.net/10356/167598
• Institution: Nanyang Technological University

Wire Arc Additive Manufacturing (WAAM) has gained prominence as a flexible and cost-effective approach for fabricating large-scale metal components with complex geometries. A critical factor in ensuring the quality and structural integrity of printed parts lies in controlling the temperature field during the WAAM process. This project investigates the temperature field variations in mild steel during the WAAM process using finite element method (FEM) simulations. A 5-layer single wall numerical model was developed, building upon a validated single-bead pass model. Material properties of mild steel, such as thermal conductivity, specific heat, and density, were taken from the validated single-bead model to ensure accuracy. Heat source parameters were also validated through experimental results, bolstering the model's reliability. Additionally, boundary conditions for the temperature field simulation were established, including initial temperature, heat source, and cooling rate. The FEM simulation offers insights into the temperature field fluctuations during the welding process under various welding power settings. By analyzing and comparing the simulation results, the project identifies the optimal welding power that ensures the quality of the printed part without causing wall collapse. This research provides valuable understanding of the relationship between welding power and temperature field variations during the WAAM process, leading to practical recommendations for process optimization and maintaining the structural integrity of manufactured parts. Furthermore, the project's findings can serve as a foundation for future research on the impact of other process parameters, such as dwell time, welding speed, and wire feed rate, on the temperature field and overall part quality in WAAM. By leveraging FEM simulations to optimize the WAAM process, manufacturers can achieve improved control over the quality of printed parts, facilitating the production of high- performance components for various industries. This project not only contributes to the body of knowledge in additive manufacturing but also promotes the development of more efficient and reliable manufacturing processes.