On Fatigue Crack Growth in a Ti-4.5Al-5Mo-1.5Cr Alloy with Metastable Beta-Phase.
Abstract
Fatigue crack growth behavior has been examined in a Ti-4.5Al-5Mo-1.5Cr alloy, for two different levels of beta-phase metastability. The resistance to fatigue crack growth appears to be marginally enhanced with the presence of metastable beta-phase in a microstructure also containing some primary alpha-phase (approx 30 pct) of high aspect ratio. This enhancement appears slightly greater for beta-phase water quenched from 899 deg C, than as more slowly cooled in helium from this same solution treatment temperature, at approximately an air-cooling rate. In the case of the former, nearly full retention of solute in the beta-phase is apparent, while in the latter, significant precipitation of secondary alpha-phase is evident in thin-foil transmission electron micrographs. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 10, 1983
- Accession Number
- ADA128048
Entities
People
- Charles M. Gilmore
- George R. Yoder
- M. Ashraf Imam
Organizations
- United States Naval Research Laboratory