Finite Element Analysis and Validation of the Superplastic Forming of Multi-Sheet Structures

This paper outlines the methods used to develop a full 3D Finite Element Model (FEM) capable of accurately predicting the superplastic forming (SPF) process of a complex multi-sheet structure. The geometry studied is a three-sheet pack consisting of an inner core sheet diffusion bonded in particular locations to two outer sheets to create a hollow internal structure when inflated. The pressure cycle implemented in the model is also used on the AFRC’s 200T press to produce parts which are compared to the model results. Comparison of 3D scans of the parts with the predicted process from the analysis reveals favorable results.