Optimal design of metallic corrugated sandwich panels with polyurea-metal laminate face sheets for simultaneous vibration attenuation and structural stiffness

With attributes such as high stiffness, high damping and lightweight, laser-welded corrugated-core (LASCOR) sandwich panels with polyurea-metal laminate (PML) face sheets were envisioned as multifunctional sandwich constructions to meet the growing needs of loading bearing and vibration/noise suppression. The sensitivity of vibration damping characteristics of these novel sandwich panels was systematically investigated using a combined finite element-modal strain energy (FE-MSE) method, and their superiority over monolithic panels having equal mass was highlighted. Subsequently, the fidelity of using the surrogate modeling technique to approximate the damping loss factor of the sandwich panel was analyzed. Under the principles of cross-validation, the orthogonal polynomial model was found to provide the most accurate predictions among four widely used surrogate models. A high-efficiency optimization procedure factoring structural stiffness, damping loss, and weight of the sandwich panel was proposed by coupling the surrogate model and an optimization algorithm. For single-objective optimization, the total weight of the optimal sandwich panel decreased by around 7% compared with that of preliminary design. Meanwhile, the Pareto fronts obtained from multi-objective optimizations revealed significant enhancements of both damping loss factor/structural stiffness and specific damping loss factor/structural stiffness.