Abstract: | The concentration of Cl− ions within pits grown on 18Cr---12Ni---2Mo---Ti austenitic stainless steel specimens immersed in vertical position in 0·5N NaCl + 0·1N H2SO4 and polarized to 860 mVNHE was studied at 20°C. The Cl− concentration within pits increases with time to a maximum and then decreases (for example, after 6 h 2N Cl− is observed). The higher accumulation of Cl− within pits, the slower their development. For slowly growing pits a maximum value of about 12N Cl− was observed. The low pH values of the solution within pits are the consequence of high Cl− contents occurring there. |