Evaluating Basalt Fabric in Stuffed Whipple and Multishock Shields Through Comparative Hypervelocity Tests

Soft goods are often used in micrometeoroid and orbital debris (MMOD) shields as means to provide targeted material properties with a relatively low areal density. In this study, basalt fabric (glass fiber made from melting volcanic rocks) is substituted for Nextel™ in two widely used MMOD shields, the multi-shock and stuffed Whipple designs. Hypervelocity testing was conducted using scaled-down versions of these two shields, and the ultimate performance (pass or fail) was compared to the predictions of the original ballistic limit equations that were derived using Nextel™ to determine if the equations can properly parametrize the basalt fabric without additional equation modification. Multi-shock shields showed comparative performance between the two different fabrics with no deviations from the prediction of performance from the ballistic limit equation (BLE) to actual observed performance. Testing on the stuffed Whipple design, however, showed conflicting results depending on the geometric scale of the tests, thus preventing a robust conclusion on the relative performance of basalt fabric in comparison to Nextel™, but suggests that the equation would still be appropriate for use with either ballistic fabric.