The possibility of decarburizing small quantities of a stainless steel in the vacuum induction furnace is demonstrated theoretically; this may lead to a way of recycling materials in small foundries. As a prelude to a thermodynamic description of vacuum decarburization and a discussion of the relevant kinetic considerations, the production parameters that influence mechanical performance (whether or not they can be control led by a vacuum treatment) are identified and quantified for GX2CrNiMoCuN25-6-3-3 austeno-ferritic stainless steeLThe thermodynamic model serves to define the conditions of pressure and temperature to be observed to extract the carbon without oxidising the chromium, and thereby attain the low carbon contents required by the standards. Under the. conditions chosen, the,kinetic approach evaluates the decarburization time at about ten minutes. Vacuum decarburization is therefore a solution that may be of value to small foundries. In addition to: improved inclusion cleanliness and lower residual gas contents, it offers, the possibility of attaining low carbon contents with an industrially viable metal treatment time.
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