scholarly journals Guidelines and procedures for design of nuclear system components at elevated temperature

1974 ◽  
Author(s):  
Keyword(s):  
Elevated Temperature ◽  
Nuclear System ◽  
System Components

Fatigue strength of autofrettaged Diesel injection system components under elevated temperature

2018 ◽  
Vol 113 ◽  
pp. 428-437 ◽  
Author(s):  
Michael Vormwald ◽  
Teresa Schlitzer ◽  
Darko Panic ◽  
Heinz Thomas Beier
Keyword(s):  
Elevated Temperature ◽  
Fatigue Strength ◽  
Injection System ◽  
Diesel Injection ◽  
System Components

Evidence for a shear mechanism for the precipitation of γ-zirconium hydride in zirconium

1978 ◽  
Vol 36 (1) ◽  
pp. 658-659
Author(s):  
G.J.C. Carpenter
Keyword(s):  
Elevated Temperature ◽  
Strain Field ◽  
Zirconium Hydride ◽  
Zirconium Atom ◽  
Atom Diffusion ◽  
Solvus Temperature ◽  
Hexagonal Close Packed ◽  
Partial Dislocations ◽  
The Face

In zirconium-hydrogen alloys, rapid cooling from an elevated temperature causes precipitation of the face-centred tetragonal (fct) phase, γZrH, in the form of needles, parallel to the close-packed <1120>zr directions (1). With low hydrogen concentrations, the hydride solvus is sufficiently low that zirconium atom diffusion cannot occur. For example, with 6 μg/g hydrogen, the solvus temperature is approximately 370 K (2), at which only the hydrogen diffuses readily. Shears are therefore necessary to produce the crystallographic transformation from hexagonal close-packed (hep) zirconium to fct hydride.The simplest mechanism for the transformation is the passage of Shockley partial dislocations having Burgers vectors (b) of the type 1/3<0110> on every second (0001)Zr plane. If the partial dislocations are in the form of loops with the same b, the crosssection of a hydride precipitate will be as shown in fig.1. A consequence of this type of transformation is that a cumulative shear, S, is produced that leads to a strain field in the surrounding zirconium matrix, as illustrated in fig.2a.

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