Method and apparatus for superplastic forming of hollow parts

Abstract

A method and apparatus for superplastic and diffusion bonding of hollow metal parts which are generally surfaces of rotation. A hollow frangible ceramic die having an interior shaping surface is provided. A metal part to be shaped is placed against the shaping surface (together with any other metal components to be diffusion bonded to the part during forming) and the remainder of the die is covered with sheet metal pieces, all of which are sealed together and to the part to form a gas-tight enclosure for the die. The enclosure is flushed with an inert gas and/or evacuated through an opening in the enclosure. The assembly is placed in an autoclave and exposed to an appropriate pressure and temperature to superplastic form the part outwardly against the shaping surface. The assembly is cooled and removed from the autoclave, then the enclosure is removed. The die is broken away, freeing the formed part.

Dependencies are inferred from the claim text.