Detection of Vacancy Concentration and Defects in Aluminum, Titanium and their Alloys and Nickel Base Superalloys by Positron Annihilation.
Final rept. Dec 73-Nov 74,
NEW ENGLAND INST RIDGEFIELD CONN
Pagination or Media Count:
Positron annihilation has been used as a tool to study the effects of defects in crystalline solids in the realm of fundamental research for a long time. This paper reports an initial effort to evaluate the usefulness and the future development of positron annihilation as a tool in non-destructive evaluation, NDE. The metals studied included Al 99.99, Al-1100, Al-2024, Ti-35A, Ti-6Al-4V, and nickel based superalloys, U-700 and M-200. The processes studied involve temperature change, work-hardening, stress-strain, creep and cyclic fatigue. The conclusion is that the process of positron annihilation is very sensitive to many kinds of defects in metals and that its potential as a tool of NDE is high. Certainly, more work is required to explore its full potential. A brief review describing the method of positron annihilation and its interaction with defects in metals is attached as an appendix.
- Metallurgy and Metallography
- Test Facilities, Equipment and Methods