An Attempt to Evaluate and Optimize the Hydroforming of Fiber Metal Laminates with the Comprehensive Forming Limit Curve

Although some papers have studied the formability of fiber metal laminates (FMLs), there is still a lack of a standard criterion for the engineering field. To give a standard for predicting the failure and provide the optimized method of the hydroforming process for FMLs, a comprehensive forming limit curve (FLC) was established by a hydro-bulging test method. The influence of pressure rate (PR), blank holder pressure (BHP), and temperature (T) was studied in this paper. Both theoretical and experimental results showed that the higher BHP and PR have a significant negative effect on limit height, while increased T has a positive effect. Moreover, the semi-cured forming of a real part was evaluated by this FLC for the very first time and the improvement suggestions of process parameters were given based on the comprehensive research. Finally, the real part that met the quality requirements was obtained by numerical simulation and trial production, which verifies the effectiveness of this comprehensive FLC.