AEROSOL PREPARATION OF COMPOSITE METAL POWDERS FOR DISPERSION STRENGTHENING. Final Report
The feasibility of utilizing aerosolization apparatus for preparing composite metal powders of value in the preparation of high-temperature dispersion-strengthened metals was demonstrated in the nickel-- alumina, nickel-- chromic oxide and tantalum--alumina systems. The aerosolization apparatus produces, from bulk powders, individually dis persed particulate clouds which at the instant of separation are individually coated with the composite-forming shell material. Refractory coatings were dispersed on micronsized preformed metal particles in order to provide materi-als analogous to the starting powders of the SAP process. Preformed submicron refractory particles acting as deposition nuclei were also coated with metal shells by gasphase chemical reaction of a volatile metal compound. After extrusion, chromic oxide particles dispersed in nickel had a mean free path of 0.5 microns. Tantalum with dispersed submicron alumina showed a mean free path of 1 micron. Judging by electron microscopic criteria, these metals should have superior high-temperature properties in fabricated shapes to the limit of stability of the dispersed phase and possibly to 0.9 of the homologous temperature. (auth)
- Research Organization:
- Aeroprojects, Inc., West Chester, Penna.
- NSA Number:
- NSA-15-017276
- OSTI ID:
- 4036836
- Report Number(s):
- NP-10061; RR-61-30
- Country of Publication:
- United States
- Language:
- English
Similar Records
Composite dispersion strengthened composite metal powders
Slurry infiltration of 3-D woven composites