Synthesis and properties of elevated temperature p/m aluminum alloys. Final report, 1 October 1981-30 September 1985

Technical Report · Sat Nov 30 00:00:00 EST 1985

OSTI ID:5686037

Fine, M E; Weertman, J R

The microstructure of the aluminum base-iron-cerium and iron-molybdenum-vanadium alloys, developed for use up to 316C, is not stable at 425C (three-quarters of the absolute melting temperature of aluminum). Metastable dispersed phases are replaced by stable phases and particles of these coarsen rather rapidly with time. Creep loading accelerates these processes. Trialuminum-zirconium was predicted to be a preferable dispersed phase for strengthening aluminum for the 425 C temperature range because of good lattice matching with the aluminum matrix giving a low interfacial energy. This is true for the thermodynamically stable tetragonal phase but especially true for the metastable cubic phase. Dilute alloys were prepared by arc melting and these were aged to form precipitate dispersed phases. Substitution of vanadium for zirconium improved the lattice parameter matching for both cubic and tetragonal trialuminum-zirconium as well as increasing the stability of the cubic form. The coarsening rates of the particles at 425 C were 100 to 1000 times slower than for the aluminum-iron-cerium or molybdenum alloys, the aluminum-zirconium-vanadium alloy being better than the binary aluminum-zirconium alloy in this respect. These alloys are very promising as the basis for better high-temperature aluminum alloys.

• Research Organization: Northwestern Univ., Evanston, IL (USA). Dept. of Materials Science and Engineering
• OSTI ID: 5686037
• Report Number(s): AD-A-164158/8/XAB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
MECHANICAL PROPERTIES
CERIUM ALLOYS
IRON ALLOYS
MOLYBDENUM ALLOYS
VANADIUM ALLOYS
ZIRCONIUM ALLOYS
CREEP
DISPERSIONS
HIGH TEMPERATURE
INTERFACES
MATRIX MATERIALS
MICROSTRUCTURE
PHASE STUDIES
STABILITY
SYNTHESIS
ALLOYS
CRYSTAL STRUCTURE
MATERIALS
RARE EARTH ALLOYS
360102* - Metals & Alloys- Structure & Phase Studies
360103 - Metals & Alloys- Mechanical Properties