Abstract: Apparatus and methods for forming an article of advanced composites on a tool forming surface from a preform are disclosed. Apparatus includes, according a preferred embodiment, a tool forming surface, a first diaphragm for urging a preform into conforming contact with the tool forming surface, and a second diaphragm for supporting a side of the preform opposite the side engaged by the first diaphragm during forming. The second diaphragm does not extend completely between the preform and the tool forming surface. The apparatus is arranged with a first diaphragm mountable on the apparatus and conformable to a preform to be formed and a second diaphragm mounted on the apparatus and conformable to a portion of the preform simultaneously with the first diaphragm. A forming tool is provided, including a tool forming surface positionable for receiving the preform between the first diaphragm and the second diaphragm when the first and second diaphragms are mounted on the apparatus.

Abstract: A system and method for reducing the occurrence of undesirable deformations (e.g., wrinkling) in a reinforced thermoformable workpiece. The reduction in undesirable deformations is achieved by increasing the buckling resistance of the workpiece by employing a supplemental reinforcing structure. The reinforcement, in combination with a pair of shaping diaphragms, increase the effective buckling resistance applied to the workpiece during the fabrication of a composite product. The method includes forming a workpiece from a plurality of layers of a thermoformable material, and applying to at least one side of the material an external reinforcing structure to form a reinforced workpiece having a top side and a bottom side. At least one of the top or bottom sides of the reinforced workpiece is placed in contact vith a diaphragm, thus forming a shaping assembly.