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The susceptibility of 17‐4PH and 17‐7PH stainless steels to stress corrosion cracking (SCC) is examined in the present investigation. The specimens were tested in the presence of NaCl and NaOH (20%) at 908C and various pH values. The evaluations were carried out using the CERT test, at a speed of 10^‐6s^‐1, supplemented by anodic polarisation and electrochemical noise analysis. The main objective was to identify the conditions of both susceptibility and performance of these materials. Fractographic analyses revealed both ductile and brittle fractures. Also, the presence of intergranular cracks was a clear indication of a characteristic anodic dissolution of the material. Nevertheless, the main mechanism for stress corrosion crack propagation was hydrogen embrittlement. From the experimental results, it was concluded that electrochemical noise analysis is a reliable technique for the identification of crack nucleation and growth.

This study attempts to investigate corrosion inhibition properties of 1H-benzimidazole (B) and 1H-benzotriazole (BTA) on aluminum in 0.25 M HCl solution at different concentrations.

To this end, electrochemical techniques including electrochemical noise (EN), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization were used.

Results showed a greater corrosion inhibition efficiency of BTA than B on aluminum in HCl solution. BTA showed greater tendency to adsorption on the metal surface than B because of the inclusion of three nitrogen atoms.

The novelty of this work is comparing EN data with EIS and potentiodynamic polarization parameters.