High sensitivity electrical resistance sensors for indoor corrosion monitoring

Abstract

It is essential that corrosion monitoring of indoor atmospheres be highly sensitive, especially when corrosion rates corresponding to the lowest standard corrosivity categories are supposed to be identified within one or a few days. The electrical resistance (ER) technique in combination with high sensitivity ER sensors enabled detection of corrosion loss on an atomic scale. The magnetron sputtering method was used to produce sensors equipped with 50 to 800 nm metallic track. The set of developed sensors represent a wide range of materials, e.g. copper, silver, iron, lead and bronze. Laboratory experiments have proven that copper and silver sensors respond to changes in relative humidity and temperature within minutes. Bronze and copper sensors are able to detect changes in concentrations of volatile organic acids, which are common pollutants of indoor atmospheres in museums.