Investigation and Synthesis of High Temperature and Increased Stiffness RSP Aluminum Alloys.
Abstract
This objective of this research is to investigate two promising systems as th basis for high temperature aluminum alloys useful to 425 C (800 F). The first is metal matrix composite consisting of an aluminum magnesium alloy matrix reinforced by spinel (magnesium aluminate) particulate. The second system is tri aluminum (zirconium, vanadium) dispersed in aluminum matrix. Here the lattice parameter matches that of the matrix. Research on dilute alloys has shown a low coarsening rate for this intermetallic at 425 C. Study of more concentrated alloys is underway. A mechanical alloying liquid metal infiltration procedure for preparing specimens of the aluminum alloy matrix spinel composite has been worked out and specimens with 4 vol% spinel have been prepared. Also, 4 vol.% alumina composite samples were prepared for comparison. Spinel particles were within the aluminum alloys grains in contrast to the alumina which was at grain boundaries. The spinel composite had much better creep resistance at 410 C. Extrusions containing 5 vol.% tri-aluminum (0.75 vanadium, 0.25 zirconium) were prepared for this research by Lockheed-Palo Alto from rapidly solidified foil. The measured creep rate at 425 C is much lower than in the current aluminum-iron-cerium alloy. An aluminum vanadium intermetallic compounds, however, forms at grain boundaries leading to a precipitate free zone which grows slowly at 425 C. Keywords: Aluminum, High temperature alloys, Aluminum-zirconium-vanadium, Aluminum spinel.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1987
- Accession Number
- ADA190407
Entities
People
- Julia R. Weertman
- Morris E. Fine
Organizations
- Northwestern University