On the anomalous temperature dependence of yield stress in β brass at low temperatures

1980 ◽  
Vol 14 (12) ◽  
pp. 1315-1318 ◽  
Author(s):  
S. Hanada ◽  
Y. Mori ◽  
O. Izumi
Keyword(s):  
Temperature Dependence ◽  
Yield Stress ◽  
Low Temperatures ◽  
Anomalous Temperature Dependence ◽  
Anomalous Temperature

Yield Stress Reversibility and the Operation of Frank-Read Sources in Li2 Alloys in the Anomalous Regime For (111) Slip

1994 ◽  
Vol 364 ◽  
Author(s):  
S. S. Ezz ◽  
P. B. Hirsch
Keyword(s):  
Strain Rate ◽  
Temperature Dependence ◽  
Yield Stress ◽  
Edge Dislocation ◽  
Anomalous Temperature Dependence ◽  
Successful Operation ◽  
Anomalous Temperature ◽  
Small Strains ◽  
Edge Dislocations ◽  
Is Strain

AbstractThe yield stress τy at small strains (≈ 0.01%) is strain rate independent, and has the same anomalous temperature dependence as that of the 0.2% strain. τy is considered to be the stress at which Frank-Read sources operate in a virgin crystal. For successful operation, τy must exceed the stress τs at which screws propagate dynamically through the crystal, and the source dislocation must pass rapidly through the unstable Frank - Read configuration. This can be achieved by the bowing edge dislocation overcoming local obstacles before reaching that configuration. Loops elongated along the screw direction are expected to be formed in the microstrain region. Under certain conditions such loops are unstable on unloading, thereby generating long edge dislocations which can operate successfully as sources at low but not at high temperatures, explaining the reversibility phenomenon.

Effect of annealing on the resistivity of self damaged plutonium

1965 ◽  
Vol 284 (1398) ◽  
pp. 344-353 ◽  
Keyword(s):  
Temperature Dependence ◽  
Point Defects ◽  
Low Temperatures ◽  
Isochronal Annealing ◽  
Anomalous Temperature Dependence ◽  
Anomalous Temperature ◽  
Annealing Stage ◽  
Accumulation Of Defects ◽  
Annealing Experiments

When samples of α plutonium are stored at low temperatures their resistivities increase owing to the accumulation of defects produced by the radioactive disintegration of the nuclei. Isochronal annealing experiments have been performed on α plutonium which show that this additional resistivity recovers in two distinct stages centred at ca . 75 and 150 °K respectively. In δ stabilized plutonium the first annealing stage is more pronounced and occurs at lower temperatures, the values of which are dependent on the concentration of aluminium used to stabilize the δ phase. Isochronal annealing experiments have also been performed on heavily damaged samples of α plutonium and yield further information on the anomalous temperature dependence of the resistivity changes brought about by self irradiation at low temperatures. The correlation between the observed resistivity changes and corresponding changes in the concentration of point defects is discussed.

Sign in / Sign up

Export Citation Format

Share Document