The superalloy was heat-treated so as to obtain various microstructures. The H permeability (table 185) and diffusivity (table 186) were then determined by using a gaseous H permeation technique to study the effect of the microstructure upon the permeation behavior at 210 to 430C. It was shown that the temperature dependences of H permeability and diffusivity obeyed an Arrhenius law, and that the precipitated strengthening phases hardly affected the H permeation and diffusion behavior.

J.Xu, X.K.Sun, Q.Q.Liu, W.X.Chen: Metallurgical Transactions A, 1994, 25[3], 539-44