Abstract: A method for providing a stop-off material on a workpiece is provided, as is an associated assembly. A maskant is provided on the workpiece such that a first portion of the workpiece is exposed and a second portion of the workpiece is covered by the maskant. The stop-off is then disposed, with the maskant on the workpiece preventing the stop-off from being applied to the second portion of the workpiece. The maskant is removed from the workpiece leaving the stop-off disposed on a select portion of the workpiece. The removal of the maskant can leave the workpiece substantially free of debris. Thereafter, the workpiece can be further processed, e.g., by diffusion bonding, with the stop-off preventing diffusion bonding of part of the workpiece.

Abstract: A method for superplastically forming a preform to manufacture a structural assembly with a contoured configuration is provided. The preform includes first and second structural members in a stacked configuration, with at least one additional peripheral member abutting the stack and joined thereto by a friction welded butt joint. In some cases, the preform defines dissimilar forming characteristics throughout, such as variations in material or thickness according to the amount of superplastic forming to be performed in each portion of the preform.