A new method for studying thermal desorption of hydrogen from metals basedon internal friction technique

Many hydrogenated pure metals and industrial alloys with FCC lattices show a distinct internal friction peak above room temperature caused by the ther mal desorption of hydrogen. Based on these observations, a new method for s tudying the hydrogen diffusivity and the interaction of hydrogen with latti ce defects is proposed for the temperature range of 250-500 K. The desorpti on origin of the peak was studied in detail in hydrogen-charged Inconel 600 alloys with different carbon contents. The peak was shown to possess trans ient and non-relaxation nature. In some cases, a fine structure of the peak caused by hydrogen traps can be observed. A theoretical model of the therm al desorption effects on the losses of mechanical energy, i.e., internal fr iction, in metals is developed.