Properties of zirconium alloys and their applications in light water reactors (LWRs) - Materials' Ageing and Degradation in Light Water Reactors - page 122

(a) 10 (b) 13

12

Total elongation
Uniform elongation

9

11
10

8

7

9
8

6

7

5

6

4

5

4

3

3

2

Total elongation
Uniform elongation

2

1

1

0 0 0 0 0 0
Radial hydride (ppm)

0 0 0 0 0 0
Radial hydride (ppm)

50 60 70 80 50 60 70

4.36 Effect of radial hydrides on elongation of Zircaloy-4 cladding
specimens with ~200 ppm hydrogen. Tested in circumferential direction
at (a) room temperature and (b) 300 ° C (573K) (Yagnik et al ., 2004).

￿ ￿ ￿ ￿ ￿ ￿

100 μ m

4.37 Typical hydride orientation in a cold worked and stress relieved
Zircaloy-4 cladding (~230 ppm hydrogen) (Chu et al ., 2008).

￿ solubility of H in the specifi c alloy at its specifi c burnup that will deter-

mine the amount of H in solution at the maximum temperature and the
amount of circumferential hydrides;
microstructure features such as grain size, amount of cold work and dis- ￿

location structures;