A review of emerging hydroforming technologies: design considerations, parametric studies, and recent innovations

Abstract Hydroforming is a modern metal-forming process prominently used in the shipbuilding, aerospace, and automotive industries for forming lightweight, complex-shaped geometries due to their inherent process benefits. But this process faces challenges such as limited material selection, high tooling costs, and complex process control for obtaining a defect-free part with uniform thickness. Researchers are constantly innovating and advancing hydroforming technologies to overcome these limitations. This work reviews emerging tube and sheet hydroforming technologies, considering parametric effects and design considerations, particularly for micro-domain applications. Further, a wider acceptance of the hydroforming process in different industries is explored by discussing the studies that tried to improve the efficiency and quality of the hydroforming process. This study observed that better formability could be achieved in hydroforming with appropriate intermediate heat treatment, proper lubrication, the correct design of loading paths, and temperature distribution. In tube hydroforming, wrinkles, necking, and cracking observed to be largely reduced by properly selecting the internal pressure and feeding. The precise protrusion height and uniform thickness at different joint cross-sections in tube forming are found to be significantly influenced by the strain-hardening exponent, loading path, and friction coefficient. Electrohydraulic forming is found being increasingly used due to its higher productivity and lower product cost. However, further research is required to achieve complex sheet geometries with sharp corners. This research emphasizes that advanced research, artificial intelligence integration, and the exploration of alternative materials can improve the performance of the hydroforming process.