The GREAC cell used to establish constitutive models for powder type materials

In this report a theoretical and experimental study of a glass powder (diameter of 40-80 μm) is made to establish a constitutive material model by using the GREAC (Gauged REActive Confinement) cell. The GREAC cell is simply a hollow cylinder were the test material is inserted and compressed axially. We show how an algorithm can be used to establish constitutive material models from the output data from the experiment. The algorithm use measurements of the axial force, the axial displacement of the glass powder and the axial and hoop strain measured at the outer surface of the GREAC cell. By comparing the assumptions in the model with well known materials we test the quality of the model. A check of the quality/accuracy of the measurements have also been done. A finite element analysis has been performed by using SolidWorks with COSMOSWorks.