Influence of chromate, molybdate and tungstate on pit formation in chloride medium |
| |
Authors: | JWJ Silva |
| |
Institution: | Electrochemistry and Corrosion Group, UNESP-São Paulo State University, Av. Dr. Ariberto Pereira da Cunha 333, CEP 12516-410, Guaratinguetá, SP, Brazil |
| |
Abstract: | It has been characterized and evaluated the 2024-T351 and 7050-T7451 aluminum alloys pitting corrosion in naturally aerated chloride aqueous solutions containing chromate, molybdate and tungstate. It has been carried out electrochemical and non-electrochemical immersion corrosion tests accompanied by surface metallography analysis using an optical microscopy. Chromate for the two alloys and in molybdate for 7050 has corrosion inhibiting effects, whereas tungstate promotes the pitting corrosion for these alloys. Quantitative surface analysis upon the alloys after immersion has indicated that pits are predominantly conical or quasi-conical and irregular. In general, pits have been wider than deep and the widest have been also the deepest. Despite inhibitor presence, when pits have been nucleated, they grow with the same intensity. |
| |
Keywords: | Aluminum alloys Aircraft alloys Pitting corrosion Image analysis |
本文献已被 ScienceDirect 等数据库收录! |
|