Atmospheric Corrosion Effects of  SO 2 and  O 3 on Laboratory‐Exposed Copper

Abstract

Copper samples were exposed for 10 days in synthetic laboratory air at 75% relative humidity. To explore the possible influence of ozone on the atmospheric corrosion rate of copper, various combinations of the gaseous pollutants sulfur dioxide, nitrogen dioxide, and ozone were added. Ozone promotes the oxidation of sulfur dioxide to sulfate more efficiently than nitrogen dioxide does. A synergism between sulfur dioxide and ozone is suggested. This synergism includes both the oxidation of sulfur dioxide by ozone and the capability of ozone to form oxides, hydroxides, or other oxygen‐containing reaction products in the presence of smaller amounts of sulfur dioxide. The synergistic effect possibly can explain the unexpectedly high corrosion rates of copper found at rural sites within the UN ECE exposure program. The rural sites are characterized by low sulfur dioxide and nitrogen dioxide concentrations, and by high ozone concentrations.

Atmospheric corrosion of Cu by UV, ozone and NaCl

“…10 It is well known that ozone is very sensitive to ultraviolet (UV), which accelerates the photolysis of ozone to create molecular dioxygen and atomic oxygen. 11,12 A combination of UV and ozone can dramatically increase corrosivity and result in fast corrosion.…”

Accelerated Testing of Electronics to Simulate Long‐Term Worldwide Environments

“…Field studies and laboratory corrosion tests have been carried out to identify not only the corrosion products of pure metals (such as Cu [17] and Ni [18]) but also the corrosion products of relevant engineering alloys (such as stainless steels [19] and Cu-Au-Sn [20]). However, few studies have been undertaken to explore the corrosion of electronic equipment and devices deployed in harsh environments (typically exposed to Class III or harsher environments).…”

Corrosion mechanism of copper immersed in ammonium sulfate solution

“…With desirable electrical conductivity, thermal conductivity, stable chemical properties, good ductility, and plasticity, copper and its alloys are widely used in the fields of electricity, electronics, transportation, energy, marine industry, etc. However, the copper would be corroded by some polluted gases and salt particulates after exposure in the ambient atmosphere, [1][2][3][4][5][6][7][8][9][10][11][12] which can reduce its service life. One of the common salt particles within the rural and industrial atmosphere is (NH 4 ) 2 SO 4 , which would be dissolved to form a thin (NH 4 ) 2 SO 4 solution layer on copper surface when the ambient humidity gets greater than the critical relative humidity of (NH 4 ) 2 SO 4 and consequently gives rise to the corrosion of copper.…”