Reusable Shape Memory Polymer (SMP) Mandrels

Cornerstone Research Group proposes a novel reusable mandrel system utilizing shape memory polymer (SMP). This technology leverages CRG's previous R&D from both commercial and governmental programs. In Phase I, CRG will develop a lab-scale prototype SMP mandrel system. The SMP mandrel will offer the Air Force a solution to the current composite fabrication and repair issues. Our goal is to provide a single mandrel system design that will allow quick transition to multiple desired mandrel shapes, maintain structural rigidity through filament-winding conditions, and then offer a simple and rapid extraction process. The proposed mandrel system would function similarly to a rubber inflatable mandrel during insertion and removal, however would offer structural rigidity like current melt-out and breakout systems during fabrication. This type of mandrel system can only be offered by using a material capable of sharp, controllable, transitioning properties. CRG's shape memory materials possess these unique property traits. CRG will begin to develop designs and calculate the forces the tooling will experience during the composite fabrication at a lab-scale to demonstrate feasibility for Phase II scale-up. The part will contain design aspects that will demonstrate the SMP mandrel system capabilities.