Stress corrosion cracking hydrides

The environments, along with the cracking modes of zirconium and titanium, are given in Table 4.88. It is obvious from the table that zirconium alloys are susceptible to stress-corrosion cracking in a variety of environments. It is necessary to subject the weld to heat treatment in order to lower the stress in the weld. The most serious problem encountered in the nuclear applications is delayed hydride cracking in addition to stress-corrosion cracking, particularly in Zr-2.5% Nb alloy. 

R. A. Gilman, The role of surface hydrides in stress corrosion cracking, Stress Corrosion Cracking and Hydrogen Embrittlement of Iron-Base Alloys, Firminy, France, June 1973 (R. W. Staehle, J. Hochmann, R. D. McCright, and J. E. Salter, eds.), NACE, Houston, 1977, p. 326. 

The stress corrosion cracking of a-titanium alloys occurs by nucleation of hydride (by the interaction of absorbed hydrogen with the metal). 

N Winzer, A Atrens, W Dietzel, G Song, KU Kainer, Evaluation of the delayed hydride cracki ng mechanism for transgranular stress corrosion cracking of magnesium alloys. Materials Science and Engineering A, 2007, 466, 18-31. 

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