The low temperature oxidation of copper

Abstract

The attack of dry air or oxygen upon copper becomes appreciable somewhere in the neighbourhood of 200° C. The mechanism of the reaction in this temperature range has been studied by a number of authors but the absence of unanimity in their conclusions is remarkable. It is evident that the oxidation of a metallic surface may result in the formation of a protective oxide film, and that continued oxidation may be controlled by the diffusion of oxygen through the film rather than by factors which are normally described as chemical. Under these circumstances the progress of oxidation is precisely similar to the flow of heat and is subject to the same laws. If c is the concentration of oxygen at a distance y from the oxide—oxygen surface after a time t then D δ 2 c /δ y 2 = δ c /δ t .