Abstract
Electrochemical systems such as SOFC, SOEC and OTM, operating in 600-1000°C temperature range, can effectively utilize alumina scale forming alloys and coatings for the construction of air handling system (heat exchanger, pipe, manifolds) to prevent or minimize chromium evaporation and related electrode poisoning. In this work, a pretreatment process that allows for the formation of predominantly alumina surface scale on an alumina forming alloy under controlled oxidation conditions is presented. Surface and cross sectional morphology show the evolution of exclusive alumina scale under developed controlled oxidation conditions when compared to oxidation in air. Mechanism for reduction in chromium evaporation from the alloy surface is presented. Oxide morphology and chemistry developed during surface pretreatment are also presented.