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Discussing dissimilar metals

Abstract
When two dissimilar metals come in contact, such as when metal fasteners are used to attach metal flashings or accessories, one of the metals has an increased potential to corrode. This is referred to as galvanic corrosion, and there are steps roof system designers can take to prevent this from occurring. Galvanic corrosion When two dissimilar metals come in contact and are exposed to a common electrolyte, one of the metals can undergo increased corrosion while the other metal can show decreased corrosion potential. Any solution containing water can be an electrolyte. Rainwater, dew and condensation are electrolytes because they contain dissolved ions from common environmental conditions. In comparison, seawater is a more conductive electrolyte and, therefore, more corrosive because of its much higher concentration of dissolved salt ions.
Date
11/2019
Author(s)
Mark Graham
Page(s)
22-24
Source
Research+Tech
Keyword(s)
metals; galvanic; corrosion; drones



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