Hybrid Experimental-Numerical Methodology for Mechanical Characterization of Materials

The displacement field of structures generally loaded and constrained is univocally defined if material properties are known. This represents the basic pillar of an inverse solution of the elastic problem, commonly used to characterize traditional materials. This paper describes a new approach for solving an inverse engineering problem to apply on innovative materials, whose mechanical properties are unknown. It works iteratively and aims to minimize the difference between the displacement field measured experimentally on three-point-bending tests and their counterpart computed by FEM analysis, applying the same loads and boundary conditions. This hybrid procedure is based on a combination of an optical interferometric technique having nanometric sensitivity (Electronic Speckle Pattern Interferometry) with a numerical procedure which uses an optimization algorithm. The purpose is to predict accurately the mechanical properties of new materials, object of interest for aerospace, biomechanical and technological industries, deeply reducing costs and time.