Mineralogical constitution of powders for continuous casting moulds

Abstract

Powder fluxes perform several key functions in the continuous casting of steel slabs, both at the surface steel product and in the control of the heat transfer during the process. The mineralogical constitution and the melting solidification behaviour of several commercial fluxes were determined to establish design parameters for the production of powder fluxes used in the continuous casting of steel slabs. The characterisation of the commercial fluxes showed that they are produced simply by mechanical mixing of base materials such as feldspars and clays. It was found that their melting behaviour depends on its chemical composition, mineralogical species contents and particle size; in particular, a change in the fluidising effect of CaF₂ was observed when the species content is >12%. Therefore, flux powders that fulfil the thermal requirements for the production of low carbon and medium carbon steels were produced from minerals available in the local market.