Yield strength of the L1/sub 2/ phase Zr/sub 3/Al. [295 and 675/sup 0/K; neutrons]

Journal Article · Sun Jan 01 00:00:00 EST 1978 · Acta Metall.; (United States)

DOI:https://doi.org/10.1016/0001-6160(78)90199-2· OSTI ID:6783206

Schulson, E M; Roy, J A

The yield strength of well-annealed, polycrystalline Zr/sub 3/Al has been measured versus temperature, strain rate and grain size. The results show that at temperatures below approx. = 875 K (for material of 5 ..mu..m grain size) yielding is controlled by dislocation generation and by the subsequent transmission of slip across grain boundaries. At higher temperatures, yielding is controlled by grain boundary sliding. Tests at 295 and 675 K show that the yield strength, sigma/sub y/, obeys the expression sigma/sub y/ = sigma/sub 0/ + k/sub y/d/sup -1/2/, where sigma/sub 0/ and k/sub y/ are experimental parameters and d is a measure of grain size: sigma/sub 0/ increases with temperature, while k/sub y/ decreases, and this causes sigma/sub y/ to increase with temperature for d > d/sub c/, but to decrease for d < d/sub c/, where d/sub c/ approx. 2 ..mu..m. At these temperatures, yielding occurs discontinuously and is accompanied by the propagation of a Luders band within which the strain, epsilon/sub L/, is given by epsilon/sub L/ = lambda d/sup -1/2/, where lambda is an experimental parameter which increases with increasing temperature. lambda is equivalent to k/sub y/theta where theta is the work-hardening rate at low strains. The positive temperature response of sigma/sub 0/ is discussed in terms of current theories of yielding in the L1/sub 2/ alloys.

• Research Organization: Chalk River Nuclear Labs., Ontario, Canada
• OSTI ID: 6783206
• Journal Information: Acta Metall.; (United States), Vol. 26:1
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
22 GENERAL STUDIES OF NUCLEAR REACTORS
ALUMINIUM ALLOYS
PHYSICAL RADIATION EFFECTS
ZIRCONIUM ALLOYS
CREEP
GRAIN SIZE
HIGH TEMPERATURE
MEDIUM TEMPERATURE
STRAIN RATE
YIELD STRENGTH
ALLOYS
CRYSTAL STRUCTURE
MECHANICAL PROPERTIES
MICROSTRUCTURE
RADIATION EFFECTS
SIZE
360106* - Metals &amp; Alloys- Radiation Effects
360103 - Metals &amp; Alloys- Mechanical Properties
220200 - Nuclear Reactor Technology- Components &amp; Accessories