Methodologies for Cost-Effective Measurement of Dynamic Material Properties for Carbon-Carbon Composites

Explosions and high-velocity impacts can create strain rates up to 106 s-1 in carbon-carbon composites (CCC). To simulate these events, first-principles codes require material models that are valid at these loading rates. Currently, the amount of test data, material models and material constants for this strain rate range is extremely limited, and an innovative and cost-effective laboratory test procedure is needed. To address this need, Protection Engineering Consultants (PEC) has teamed with Southwest Research Institute (SwRI) to evaluate existing high-rate loading procedures that could be applied to CCC and to develop improvements for strain rates up to 106 s-1 and temperatures up to 1,000 oC. The goal is to measure the equation of state, Hugoniot Elastic Limit, spall strength, fracture toughness, and energy release rate. These improved procedures and associated hardware designs will be implemented in Phase II. Limited laboratory testing will be performed in Phase I to demonstrate potential for some of the methods. PEC will evaluate existing constitutive models to determine if they can be extended to these extreme loading rates; if not, modifications or new models will be proposed. Approved for Public Release | 18-MDA-9817 (23 Oct 18) Explosions and high-velocity impacts can create strain rates up to 106 s-1 in carbon-carbon composites (CCC). To simulate these events, first-principles codes require material models that are valid at these loading rates. Currently, the amount of test data, material models and material constants for this strain rate range is extremely limited, and an innovative and cost-effective laboratory test procedure is needed. To address this need, Protection Engineering Consultants (PEC) has teamed with Southwest Research Institute (SwRI) to evaluate existing high-rate loading procedures that could be applied to CCC and to develop improvements for strain rates up to 106 s-1 and temperatures up to 1,000 oC. The goal is to measure the equation of state, Hugoniot Elastic Limit, spall strength, fracture toughness, and energy release rate. These improved procedures and associated hardware designs will be implemented in Phase II. Limited laboratory testing will be performed in Phase I to demonstrate potential for some of the methods. PEC will evaluate existing constitutive models to determine if they can be extended to these extreme loading rates; if not, modifications or new models will be proposed. Approved for Public Release | 18-MDA-9817 (23 Oct 18)