Multi-Material Structures (MSC P4020)

Minimizing corrosion is a constant challenge to the ship design community. Fiber-reinforced polymers are generally corrosion resistant; in fact glass fiber reinforced composites may be fastened or joined with almost any fastener material to metals without fear of galvanic corrosion. However, carbon fiber reinforced composites, which may be necessary to achieve strength and stiffness performance goals, can induce galvanic corrosion in the attached metal structures, or metal fasteners. In this proposal, Materials Sciences Corporation presents a combined analytical and experimental plan for demonstrating the performance potential of hybrid composite structural components of interest to the undersea Navy. Here, the term hybrid is used to describe a composite manufactured using both carbon and glass fibers, either in general layered configurations or discrete transition areas of a structural component. Two important technical issues will be addressed for two out-of-autoclave material processing systems of interest to the U .S. Navy; viz., evaluation of processing induced stresses due to dissimilar material stiffnesses and selection of lamination architectures that provide the best balance of strength and durability. Coupon, element, component and full-scale elements will be manufactured and tested to validate translation of individual material properties to hybrid structures. Results of this program will add to what has been called"Best Practice"design guidance for composite non-pressure hull submarine components.