Superplastic Forming & Diffusion Bonding of CORONA 5.
Abstract
The processing of CORONA 5 (Ti-4.5 Al-5 Mo-1.5 Cr) to cold-rolled sheet and the subsequent evaluation of this sheet for superplastic formability, diffusion bondability and post-forming heat treatment response is discussed. Two heats of CORONA 5, one of 'standard' oxygen content (0.183 wt %) and one of low oxygen content (0.085 wt %) were processed to fine-grained, 0.07 in (1.8 mm) sheet and limited characterization of the sheet material conducted. Superplastic properties were determined at 843, 871 and 899 C; diffusion bonding parameters were predicted for all three temperatures and evaluated at 871 C. Adequate superplastic properties were observed at all temperatures with the lower temperatures exhibiting better properties. The optimum superplastic forming and diffusion bonding temperature was found to be 871 C, particularly for low oxygen material. Pan forming tests at all three temperatures and the expanded sandwich test at 871 C confirmed these observations. The results of the program have demonstrated that by controlling the oxygen content of CORONA 5 and by processing to a small grain size, a highly desirable combination of SPF/DB response and post-forming tensile properties could be obtained and that the alloy is amenable to sheet processing using a continuous-strip process.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1981
- Accession Number
- ADA102206
Entities
People
- C. F. Yolton
- C. H. Hamilton
- J. C. Chesnutt