A new model to determine the hardness of thin films
Résumé
Hydrogen embrittlement is mechanical properties deterioration phenomenon for steels, especially those possessing higher mechanical resistance. The steels microstructure plays an important role on the susceptibility to hydrogen embrittlement and its characterization requires the knowledge of the steels hydrogen permeation physical parameters. This work had the objective to determine the hydrogen permeation kinetics through quenched-andtempered carbon steel that was heat treated in two different conditions in order to obtain distinctly different tempered martensite microstructures. This was carried on by performing electrochemical hydrogen permeation tests at 20oC, using 0.1N NaOH solution as electrolyte. It was observed that the microstructure resultant from the tempering heat treatment at the lower temperature yielded slower hydrogen diffusion kinetics and a greater value for the hydrogen solubility due to the presence of irreversible hydrogen trap sites at the test temperature.