Hydrogen-induced cracking of pure titanium in sulphuric acid and hydrochloric acid solutions using constant load method

The hydrogen-induced cracking (HIC) of the commercial pure titanium (Ti) has been investigated as functions of applied stress and test temperature in sulphuric acid and hydrochloric acid solutions by using a constant load method. From the results obtained, HIC was hydrogen embrittlement (HE) related to the fracture of hydride. We have also found that the steady state elongation rate obtained from corrosion elongation curve becomes a relevant parameter for predicting time to failure and a criterion to assess whether HIC takes place or not. A parameter, tsstf−1 was also found to become an indicator to assess whether HE takes place or not. Furthermore, it was deduced that HIC was qualitatively explained in terms of hydride formation and a localized deformation, which was basically based on a hydride formation-rupture event at crack tips.