Abstract

ALUJAS DIAZ, Adrián et al. Productos De La Reducción Carbotérmica De Cromita Refractaria A Baja Temperatura, Una Fuente Alternativa En El Tratamiento Cromodifusivo De Aceros. Rev. LatinAm. Met. Mat. [online]. 2003, vol.23, n.2, pp.03-11. ISSN 0255-6952.

In this work is presented a method for the obtention and characterization of a carbothermical prereduced product, using as base material a concentrate of cuban refractory chromite. The study of the reduced mixture is carried out to explore the possibilities of use of the reduction products as suitable components of mixtures for the obtaining of chromium carbides layers in steels through the thermodifusion method. The reduction is carried out for a mixture with high compactation degree and to a temperature of 1000 ° C. In the characterization of the chromite concentrate it was found that by its chemical and structural composition it can act simultaneously as carrier of the active component and of the thermorefractory additives in the chromodifusive mixture, with a chromium / silicon relation in correspondence with the recomended values for chromodifusion mixtures. In the characterization of the prereduced mixtures by Infrared Spectroscopy, Mössbauer Spectroscopy and X-Ray Difraction techniques, the presence of metallic carbides ( (Cr,Fe)₂₃ C₆ , (Cr,Fe)₇ C₃ ) was detected, characteristic of advanced stages of the reduction process and with possibilities to act as chromium difusors. It was found tahat the addiction of CaCO₃ to the mixture allow better reduction conditions.

Keywords : refractory chromite; carbothermic reduction; thermodifusive treatment.