Materials Evaluation. Part II. Development of Corrosion Inhibitors.
Abstract
A borax-nitrite based inhibitor has been developed for incorporation into the Air Force Rinse Facility at MacDill Air Force Base. Chromate-based products, in combination with polyphosphates, have been reasonably effective against corrosion of ferrous and nonferrous metals and alloys and are presently the most widely used inhibitors. However, the use of chromates has been the subject of ecological concern, and the investigation discussed herein involves alternatives to chromates. The performance of nonchromate commercial inhibitors has been tested and a borax-nitrite based formulation developed which inhibits the corrosion of several ferrous and nonferrous metals and alloys. This mixture contains no chromates and offers important advantages over the chromate-polyphosphate combination. Corrosion-fatigue and crack-growth studies on aluminum alloys have shown a reduction of more than one order of magnitude in crack-growth rate in the presence of this inhibitor. Infact, the crack growth decelerates to the air-sample level with the use of the inhibitor, even in an aqueous environment of 0.1M NaCl solution. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1979
- Accession Number
- ADA080905
Entities
People
- M. Khobaib