The Microstructural and Phase Characterization of RST A1-Ti-X Alloys
Abstract
Powder Metallurgy A1-4 wt. % Ti and A1-6 wt. % Ti alloys have demonstrated potential for elevated temperature (200-300 C) aircraft applications. These materials derive their excellent strength, ductility, and creep resistance from their fine grain structure, oxide dispersion, and A1 Ti intermetallics. Inert gas atomization and mechanical alloying have been used to produce the binary alloy powders; however, Because of the large solidification range (1200-665 C) large quantities of primary A13 Ti were produced. In this study A1-Ti, A1-TiCe, and A1-Ti-V alloy powders were produced by melt spinning. The alloys were fully characterized in order to assess the effect of composition and processing conditions on microstructure and phase stability. Optical and electron microscopy was used to study the morphology and distribution of second phase disperoids. X-ray diffraction, differential scanning calorimetry (DSC), and selected area electron diffraction (SAD) techniques were used to establish the crystallography of the phases present. The microstructure of the melt spun A1-Ti-X alloys have a higher volume fraction of finely dispersed submicron aluminides than did the previously studied inert gas atomized alloy powders. The major phases identified included A1 (fcc), A13 Ti(14/mmm), and A13 Ti (14/mmm). Keywords: Rapid solidification, Aluminum, Titanium, Aluminum alloys, Vanadumm, Cerium, Titanium alloys.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1988
- Accession Number
- ADA203734
Entities
People
- James J. Thompson
- William E. Frazier
Organizations
- Naval Air Warfare Center Warminster