Previous work by the Air Force Research Laboratory's Composites Branch (AFRL/RXCC) has shown that knowledge of the material characteristics during cure is needed to accurately predict the spring-in behavior observed in fiber-reinforced polymer matrix composite of minimal complexity, such as L-shaped angle brackets. Sensitivity studies indicate the resin material models, particularly for cure shrinkage (CS) and coefficient of thermal expansion (CTE), are key components in successfully simulating the resultant deformation. Resin CS and CTE are tightly coupled models as they jointly define resin specific volume as a function of temperature and degree of cure. In this effort, a novel experimental approach for measuring cure shrinkage is detailed using a simple bi-material strip (BMS), comprised of a cast resin film on a thin strip of metal, and two-dimensional digital image correlation (2D DIC) to capture displacements while the strip is subjected to a specific temperature cycle. This paper will discuss the development and efficacy of the novel experimental technique in comparison with measurements gathered using volumetric dilatometry.
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