Investigation of forming optimization of composite tubes based on liquid impact forming

Liquid impact forming (LIF), a composite forming technology of metal thin-walled tubes based on tube hydroforming (THF) and stamping forming, is introduced to increase the forming efficiency and decrease the cost. In this paper, a finite element model was established to study the forming characteristics of composite tubes under different mold cavities and clamping speeds. Then, the effects of different loading parameters on the bulging height, fillet radius and wall thickness distribution of composite tubes were analyzed systematically. Furthermore, the main factors affecting the formability of the tube were investigated based on response surface method (RSM), with the wall thickness variance, bulging height and fillet radius of the tube designed as targets, the mold side length, clamping speed and initial internal pressure selected as variables, the optimal loading parameters were obtained. At last, experiments of composite tubes based on the optimized loading parameters were conducted. The results showed that the deviation between the experimental results and the numerical simulation was within 5%, which verified the accuracy and reliability of the parameter optimization results.