Fundamentals and Processes of Fluid Pressure Forming Technology for Complex Thin-Walled Components

A new generation of fluid pressure forming technology has been developed for the three typical structures of tubes, sheets, and shells, and hard-to-deform material components that are urgently needed for aerospace, aircraft, automobile, and high-speed train industries. In this paper, an overall review is introduced on the state of the art in fundamentals and processes for lower-pressure hydroforming of tubular components, double-sided pressure hydroforming of sheet components, die-less hydroforming of ellipsoidal shells, and dual hardening hot medium forming of hard-to-deform materials. Particular attention is paid to deformation behavior, stress state adjustment, defect prevention, and typical applications. In addition, future development directions of fluid pressure forming technology are discussed, including hyper lower-loading forming for ultra-large non-uniform components, precision forming for intermetallic compound and high-entropy alloy components, intelligent process and equipment, and precise finite element simulation of inhomogeneous and strong anisotropic thin shells.