Author’s 2nd reply to comments on author’s reply to “Review of the thermodynamic basis for models of delayed hydride cracking rate in zirconium alloys,” M.P. Puls in J. Nucl. Mater. 393 (2009) 350–367

The aim of this work is a second reply to Puls’s comments on the author’s first reply to the paper published in J. Nucl. Mater. 393 (2009) 350–367. The Dutton–Puls model indicates that the CGR is governed not by the stress gradient but by the ΔC that results from a decrease in the crack tip solubility due to the stress when compared to the bulk solubility, demonstrating that Puls’s defense of the Dutton–Puls model is inconsistent and invalid. Given the fact that DHC involves three consecutive processes such as nucleation, growth and cracking of hydrides at the crack tip, Puls’s claim that DHC is simply a diffusion-controlled process and the CGR is governed solely by the rate of hydride growth is incorrect, yielding many of the unsolved issues related to DHC. It is confirmed that Kim’s criticism that the Dutton–Puls model for the crack growth rate (CGR) is established based on a faulty thermodynamic basis is correct.