7. Use of VFM for Heterogeneity Evaluation of Materials Under Uniaxial Tensile Stress

Identification of spatially varying stiffness is a challenging, but important, research topic especially as materials become more complex and are used in extreme environments. Examination of heterogeneity is often accomplished by unique test fixtures capable of creating the necessary stress configurations for heterogeneous stiffness identification. In this work the Virtual Fields Method (VFM) was used to identify stiffnesses in a simple geometry, namely uniaxial tension, of a simulated material with an inclusion whose stiffness gradually increases from that of surrounding material. Three different VFM analyses were examined and their results compared. Results suggest that cooperative use of these analyses could provide reasonable stiffness identification for heterogeneous materials using uniaxial tensile tests.