Chapter 8 - Adhesive Bonding and Integrally Cocured Structure

Abstract

This chapter discusses adhesive bonding and integrally co-cured structure. Adhesive bonding is a method of joining structures together that eliminates some, or all, of the cost and weight of mechanical fasteners. In adhesive bonding, cured composites or metals are adhesively bonded to other cured composites, honeycomb core, foam core, or metallic pieces, whereas co-curing is a process in which uncured composite plies are cured and bonded simultaneously during the same cure cycle to either core materials or other composite parts. Thin structures with stiff and well-defined load paths are joined by adhesive bonding, while thicker structures with complex load paths are joined by mechanical fastening. The chapter discusses the most critical fabrication aspect of bonding, that is, surface preparation. Without proper surface preparation, the long-term durability of the joint will not be realized. Co-cured unitized structure is another option for reducing assembly costs. Although it eliminates some of the potential durability costs associated with honeycomb, it is more difficult to design and more costly to tool than honeycomb assemblies.