In many applications cold rolling is the final manufacturing step of stainless steels. Beside the beneficial strengthening effects of cold deformation, such process may alter the pitting corrosion susceptibility of stainless steels (1, 2). In the present study the effect of cold rolling on pitting corrosion of 17-4 precipitation hardening stainless steel in 3.5% NaCl solution has been investigated. The steel was solution treated at 1050 °C for 1 hr, and then it was rolled at room temperature with final reduction of 10%, 30%, 50% and 70% in thickness. A nondeformed specimen (named as ST in figures) was also considered for comparison. Alloy microstructure was examined using SEM. Potentiodynamic and potentiostatic polarization experiments were carried out to investigate the pitting potential, the frequency of occurrence and the stability product of metastable pits as a function of cold rolling. Statistical approach was also employed to examine the effect of cold rolling on pitting potential.

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