The invention belongs to the technical field of
metal plastic
processing, and aims at providing a superplastic forming /
diffusion bonding forming method for a heat-resistant
titanium alloy envelope with high material utilization ratio, high dimension control precision and high product performance. As a mould is adopted to control the appearance and dimension of a workpiece, the forming of a
titanium alloy workpiece provided with a complex profile is completed, the production process of the heat-resistant envelope workpiece is shortened, and production cost is lowered; as the process of
diffusion bonding followed by superplastic forming is adopted, the
diffusion bonding is realized at the contact part of an
inner envelope and an outer envelope, and the superplastic forming is realized at a separated part, the once-formed heat-resistant envelope with the complex profile and a hollow structure has the advantages of greatly improved
structural integrity of a component, enhanced
specific strength and specific stiffness of the component and increased
welding rate of the
diffusion bonding; the processed workpiece has the advantages of high dimension accuracy, high integral performance, light weight and the like; and the method disclosed by the invention has the advantages of shortened
processing period, high material utilization ratio and lowered production cost.