Decarburization of an Iron-0.8% Carbon Alloy in the Presence of a Wustile Scale

Abstract

<p>The kinetics of the oxidation and decarburization of an iron-0.8% carbon alloy in carbon dioxide at 950°C have been studied. Both processes are controlled by surface reactions. Decarburization through the wustite scale has been studied by allowing oxide reduction by carbon to proceed under vacuum and in argon atmosphere . Oxide reduction is influenced both by surface reaction steps and by carbon diffusion in the metal. Transport of the gaseous reaction products through the scale is accomplished primarily by porosity in the oxide, with occasional evidence of mechanical failure of wustite. The effectiveness of the pores as a means of transport of carbon gases is dependent on the wustite scale thickness and a critical concentration of carbon at the metal-oxide interface.</p>