Gradient Functionality, Nanocomposite Elastomer Sheath System for Composite Rotor

"Metal protective sheaths currently used on the V-22 rotor blade leading edge to protect against sand and rain erosion are heavy, rigid and expensive. Elastomeric sheaths are being considered as replacements for metal sheaths, since they are lightweight,flexible and abrasion-resistant. However, elastomeric sheaths tested to date have exhibited delamination and creep failure caused by sand and rain droplet impact damage coupled with high centrifugal loads. Foster-Miller proposes to develop a gradientfunctionality, nanocomposite elastomer sheath system, called NESS, that addresses each of these issues. The NESS design provides for the highest sand and rain erosion-resistance, reinforcement against centrifugal shear forces and protection against raindroplet impact damage. NESS can be manufactured using a low-cost, automated Resin Transfer Molding (RTM) process, is lightweight, non-conductive and durable enough to resist the environments that currently cause premature sheath failure. In Phase I, wewill apply computer modeling to identify candidate NESS materials, produce NESS test specimens and evaluate NESS specimens for key properties; such as, adhesion, sand and rain erosion-resistance and creep-resistance. The Phase I Foster-Miller team includesexperts in computer modeling, nanocomposites, abrasion-resistant elastomers and helicopter rotor blade design, as well as a commercial helicopter manufacturer and a polyurethane supplier.