IN-PLANE MECHANICAL PROPERTY AND DAMAGE CHARACTERIZATION OF GLASS EPOXY COMPOSITES FOR MATERIAL MODELLING

Researcher(s)

  • Lucas Castle, Mechanical Engineering, University of Delaware

Faculty Mentor(s)

  • Sagar Doshi, Center for Composite Materials, University of Delaware
  • Jack Gillespie, Center for Composite Materials, University of Delaware

Abstract

One of the iCREATE project’s goals is to computationally simulate composites’ mechanical response under low velocity impacts. It can be done using the MAT_213 material modeling method, which relates the calculated strains on the composite to applied stresses. For this model to be completed, experimental modulus data about the composite is required. Our poster overviews the process of collecting some of this data. The orthotropic model requires modulus data for tension, compression, shear, and off-axis in all main directions. A glass epoxy composite panel was manufactured out of RDL-RDC resin and plain weave S2glass fiber using VARTM. Samples were cut from this panel for monotonic and cyclic tension testing in the longitudinal and transverse directions while leaving some for compression applications. These tests were done to allow a full damage model of the composite in tension to be gathered. Strain gages and an acoustic sensor were adhered to the sample to measure the sample’s strain and initiate and quantify the damage. Currently, just the monotonic tests for longitudinal and transverse, as well as the cyclic tests for longitudinal, have been completed. Afterward, a full data analysis was performed on the samples to determine the maximum stress and the tensile modulus. For the cyclic samples, a full analysis of all the loading and unloading modulus for all the cycles was also done to determine if there was any hysteresis. The analysis was done over varying ranges of microstrains, including the entire stress-strain curve. This analysis allowed for all of these values to be inputted into the material model and get it closer to completion. The next steps to continue on the material model would be to run cyclic tests on transverse samples as well as complete compression testing.