| abstract |
An improved method is disclosed for forming articles, especially airfoils, comprised of a fiber reinforced plastic bonded to a metal object. In the manufacture of a propeller blade a subassembly is made by coating a metal spar with a certain class of adhesive to a depth of 127-1016 microns to compensate for dimensional variations in the spar surface, transferably coating the interior of a subassembly mold with the adhesive, then inserting the coated spar into the mold and injecting a lightweight filler material. The adhesive and filler are then precured and the subassembly removed from the mold. A fibrous reinforcing material, such as glass fiber cloth, is then used to cover or wrap the subassembly, the subassembly thus covered is placed in a second mold, and a synthetic polymeric material such as epoxy resin, previously or subsequently applied, is then cured. In the formation of other articles, the filler material might be entirely omitted, and the reinforcing fibers would be separated from a metal substrate only by the precured adhesive. |