Reply to E.M. Gutman's: “comments on the “stress corrosion cracking of zirconium and zircaloy-4 in halide aqueous solutions” by S.B. Farina, G.S. Duffo, J.R. Galvele”

The present “comments” are a sequel to the previously published “notes” by the same author and on the same subject. The intention of the present correspondence is to show that the surface mobility SCC mechanism is far simpler than the description made by Gutman in his comments. It must also be reminded that in 1987, by using this mechanism, it was predicted that the presence of hydrogen in metals produced an increase in the vacancy concentration in those metals. This fact was confirmed in independent studies, and it is considered of high significance in hydrogen embrittlement.