Multi-Scale Strain Measurements of a Polymeric Material
Abstract
It is well known that, on the microscopic scale, polymeric materials may be' considered inhomogeneous materials. When these materials are stretched, the different crosslinking densities of polymeric chains can produce highly nonhomogeneous local stress and strength fields. Depending on the magnitude of the local stress and the local strength, damage can be developed in the material. The damage developed in the material may be in the form of microvoids or microcracks in the mater. The developed damage will not be confined to a specific location; rather, it will diffuse into a relatively large area or zone. The growth of damage in the material may take place by tearing the material or by successive nucleation and coalescence of the microvoids. These damage processes are time dependent and are the main factor responsible for the time sensitivity of strength degradation as well as the fracture behavior of the material. Therefore, in order to gain an advanced understanding of the failure process in these materials, a detailed knowledge of deformation process as well as damage initiation and evolution mechanisms are required. In this study, the strain fields, on the meso and macro scales, in a polymeric material, Solithane 113, were determined using Speckle Interferometry with Electron Midroscope (SIEM). The size of the region in which the strain fields were determined varied from 2.5 mm x 2 mm to 0.065 mm x 0.055 mm. Experimental data were analyzed and the results are discussed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 11, 2003
- Accession Number
- ADA410828
Entities
People
- Chun Ting Liu
- Fu-pen Chiang
Organizations
- Air Force Research Laboratory