Patent ID: 7850058

Claim:
A method for diffusion bonding and superplastically forming a pack to produce a structural assembly having a predetermined configuration, the method comprising: providing the pack comprising first and second titanium sheets in a stacked configuration, the first sheet having a grain size that is at least about twice a grain size of the second sheet; diffusion bonding portions of the first and second sheets at a temperature of less than 1500° F.; heating the pack following diffusion bonding to at least a superplastic forming temperature of the second sheet; and superplastically forming the second sheet of the pack to a predetermined configuration and thereby forming the assembly, wherein said superplastically forming step comprises forming a first structural sub-assembly and further comprising: repeating said providing, heating, and superplastically forming steps to form a second structural sub-assembly; and joining the first and second sub-assemblies to opposite transverse edges of a third sub-assembly defining transversely extending channels to form an engine exhaust heat shield, wherein each of the first and second sub-assemblies defines transversely extending cells, the cells of the first and second sub-assemblies being longitudinally offset from the channels of the third sub-assembly such that at least some of the cells of the first and second sub-assemblies are positioned to alternate in a longitudinal direction with at least some of the channels of the third sub-assembly.