The lateral growth strain accompanying the formation of a thermally grown oxide

The high-temperature oxidation of alloys produces an oxide that grows laterally as well as thickening with time. Constrained by the underlying alloy being oxidized, the lateral strain produces a compressive stress in the growing oxide. The lateral growth strain is modeled using a dislocation climb process in which "unlucky" counter-diffusing cations and anions are trapped at cores of dislocations. The model predicts that at a fixed oxidation temperature the lateral growth strain rate increases linearly with the oxide thickening rate in accord with observations. (C) 2002 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.