| 摘要 |
A method of forming metallic structures that consists of immersing shaping dies with a blank workpiece sandwiched between them in a molten metal or alloy bath at a temperature within the superplastic temperature range of the workpiece. The pressure necessary for forming the workpiece is then applied by using weights or other means disposed over the dies. The workpiece is allowed to be formed by the gravitational force of the weights while it is maintained in a superplastic state. A metal or alloy that is free of harmful elements and contaminants that cause damage to the physical properties of the workpiece and that has a melting point below the superplasticity range of the workpiece is suitable for the molten bath. The molten metal serves the dual purpose of displacing all contaminants from the surface of the workpiece and of providing a conductive source of heat for raising the temperature of the workpiece to its superplastic range. Because of the contamination-free environment, very high working temperatures are permitted by this process and, correspondingly, relatively low loading pressures are required to achieve the desired deformation; thus, if necessary, relatively long process times are available for producing exact and intricate configurations that cannot otherwise be successfully obtained.
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