Finite Element Analysis of Hemispherical-Shape Parts in the Hot Gas Bulge-Forming of Polycarbonate (PC) Sheet

Abstract

To explore geometrical shape deforms, stress distribution, strain distribution and wall thickness of products in the process of polycarbonate (PC) hot gas pressure bulging, numerical simulation of 1mm thick hemispherical PC part with a diameter of 100mm has been conducted by the software of DYNAFORM. The result shows that abrupt changes tend to occur in the deforming of PC sheet as the even loaded pressure increases to a given point. A critical circle exists in the photoelastic experiment of latitude strain distribution, wall thickness distribution and displacement change, thus making the wall thickness of hemispherical part become gradually thick from critical circle part to pressure-pad-circle part. Importantly the experimental result fits well with the finite element analysis.