Effect of Soft Core Thickness with Composite Face Sheets on Sandwich Panel Beyond Its Yield Limit

Abstract

Various industries have used sandwich panels in a vast array of applications. It is the composition that makes them unique; a low density core material, placed in between two high modulus face sheets creates an ultra-light weight structure providing extraordinary stiffness. The inner, generally softer than the face sheets has been widely studied in elastic range with metal faces often used. This study also makes a unique contribution in that it explores the impact of varying thickness of light core on the behavioral changes seen among sandwich panels after yield stress. Load grows gradually in a quasi-static process until vanishingly close to the yield point. Through using of a finite element analysis package, particularly ANSYS model this panel acquires simply supported boundary conditions on all sides. The accuracy of the developed model is proved by detecting careful comparisons with available numerical and experimental cases described in literature, demonstrating a strong concordance with previous works. Challenging conventional wisdom, this study highlights an intriguing revelation: It shows an upward variation beyond the yield strength of this central material. Interestingly, when the thickness of core increases, there is an increase in transmitted load to face sheets. Instead, a decreasing core thickness makes the sandwiched panel performance similar to that of orthotropic composite plate approaching yield before faces do.