Project Themis. Metal Deformation Processing.
Annual rept. no. 2, 1 Sep 69-31 Aug 70,
KENTUCKY UNIV LEXINGTON
Pagination or Media Count:
Uniaxial tension tests on Ti-50A and stress relaxation tests on Ti-35A have been shown to yield data appropriate for use in metalworking equations. The yield point normally observed for fine-grained Ti-35A was eliminated by prior hydrostatic pressure soaking. Creep and tensile test data on Ti-55A, Ti-75A, and Ti-6Al-4V collected from the literature were correlated through a hyperbolic sine relationship for strain rate. Superplastic behavior was obtained from 700 to 1000C for Ti-6Al-4V with an interphase spacing of 1.9 to 13.5 microns. The structures which develop in Beta III Ti upon water quenching and aging were investigated by transmission electron microscopy. A new method based on a least squares analysis was developed to compute Fourier coefficients of x-ray diffraction profiles. Both single and double maximum visioplasticity flow patterns were observed in extrusion of 2024 Al, Ti-50A, and Ti-6Al-4V at elevated temperatures. The transition from one type to the other occurred at a relatively constant value of a temperature compensated rate parameter. When reduced to mean effective stress and mean effective strain rate, the extrusion dynamics for Ti-50A and Ti-6Al-4V were found to be in reasonable accord with the deformation dynamics in axial loading. A detailed optical and transmission electron microscopy study was made of the microstructures in Ti-6Al-4V rods extruded at 735 to 1177C. Author
- Properties of Metals and Alloys
- Fabrication Metallurgy