Research Projects

Additive manufacturing (AM) has revolutionised the production of components with complex geometries that are difficult to fabricate using traditional manufacturing processes. However, poor surface quality remains a critical challenge that can limit the mechanical performance of these components, such as degraded tribological properties, thus hindering the widespread adoption of AM parts. A variety of post-processing methods, including mechanical polishing, laser-based, and chemical methods, have been developed to improve the surface finish of these parts. However, these processes are mostly limited to simpler geometries and external surfaces. The present research project proposes the utilization of ultrasonic cavitations for the surface finishing of both internal and external surfaces of metal AM parts. The primary objectives of this study are as follows: - Develop an ultrasonic cavitation-assisted abrasive process to finish both the internal and external surfaces of metal AM parts. - Investigate the efficacy of the process for improving the mechanical performance of parts, such as tribological performance. - Examine the feasibility of the developed process for finishing internal surfaces, such as holes, of metal AM parts. - Develop a theoretical framework to understand the complex relationship between process parameters such as ultrasonic amplitude, stand-off distance, and processing duration, and abrasive parameters such as grit size and abrasive concentration on the finishing mechanism and surface quality. The objectives of the project will be achieved by conducting experimental and theoretical investigations. The proposed project will be executed in the following phases: - In phase 1, the focus will be on the development of the ultrasonic cavitation-assisted surface finishing process. Various finishing media will be prepared and characterised. Both the cavitation and abrasive parameters will be optimised. - In phase 2, the developed ultrasonic cavitation-assisted finishing process will be used to finish the surfaces of metal AM parts. Surface mechanical properties such as surface finish, hardness, residual stress, and tribological properties will be evaluated and compared with the properties of the as-built parts. The feasibility of the process for finishing internal surfaces, such as holes, will be investigated. - Finally, in phase 3, numerical investigations will be conducted to understand the complex relationship between various process parameters and the surface finishing mechanism, and a theoretical framework will be established. The impact of the project is that it proposes a way to address the critical issue of poor surface quality of parts fabricated by additive manufacturing. The successful implementation of this project will result in parts with improved surface properties, subsequently enhancing their mechanical performance, thereby broadening their increased adoption in various sectors.