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

To meet MDA’s need for cost effective dynamic material evaluation techniques, Mentis Sciences Inc. proposes to modify a Split Hopkinson Pressure Bar (SHPB) apparatus to achieve and gather dynamic material response data at strain rates above 107s-1 and at temperatures up to and exceeding 1000°C to provide data for first-principles hydro-codes modeling in a laboratory environment. The focus in Phase I will be on compressive testing only, however based on these technologies there are opportunities for tensile and pressure-shear testing that will be pursued in future work, allowing for a more complete material characterization under these conditions. At the conclusion of Phase I work, all of the technical objectives will be met. Specifically, the approach, theory and data reduction methodologies will be developed and shown through numerical and analytical modeling. Mentis will demonstrate a shuttlecock striker bar on a standard SHPB apparatus. Plans for a non-contact optical strain measurement system with capability to gather data at ultra-high strain rates will be completed, and a design for a short SHPB test system that works with an ultra-high temperature chamber will be ready to fabricate under Phase II. Approved for Public Release | 18-MDA-9817 (23 Oct 18)