The Influence of Tensile Stress Affects the Ability of Corrosion Resistance

This research investigated the influence of tensile stress on corrosion resistance. The specimens used were
titanium alloys (Ti-6Al-4V, Grade 5). Tensile tests were conducted at stress levels of 350 MPa, 550 MPa, and 750 MPa sequentially. Following the tensile testing, the specimens were subjected to potentiodynamic polarization testing in NaCl (0.05 M) and Hank's Balanced Salt Solution (HBSS), controlling the potential between -3 to 3 V at a scanning rate of 10 mV/s. The reference electrode (RE) was Ag/AgCl, the counter electrode (CE) was a platinum sheet, and the working electrode (WE) was the specimen. The study found that Ti-6Al-4V specimens subjected to 350 MPa tensile stress had corrosion potential (Ecorr) values of -0.471 V (NaCl) and -0.446 V (HBSS), which were higher than those of specimens subjected to 550 MPa and 750 MPa tensile stress. The Ecorr values for the 550 MPa stress group were -0.666 V (NaCl) and -0.503 V (HBSS), and for the 750 MPa stress group, the values were -0.701 V (NaCl) and -0.603 V (HBSS). Specimens subjected to increased tensile stress exhibited decreased corrosion potential, likely due to surface failure caused by the tension.