ホスホン酸系溶液中における銅の孔食に及ぼすCl^-の影響

抄録

The pitting corrosion of copper in cold water containing inhibitors composed of nitrilotris methylene triphosphonic acid (ATMP), benzotriazole (BTA) and zinc sulfate (ZnSO₄) has been studied using immersion tests and electrochemical measurements. The results obtained are summarized as follows: 1) Pitting corrosion was influenced by SO₄^2- rather than Cl^-. 2) The presence of both SO₄^2- and Cl^- in ATMP+BTA solution was conducive to pitting corrosion. 3) In ATMP+BTA solutions containg SO₄^2-, breakdown potential E_b was linearly dependent on Cl^- and is thought to affect the critical breakdown potential.