Procesado térmico de moldes confeccionados con revestimiento de joyería mediante microondas por calentamiento híbrido

Abstract

This research aims to contribute to the understanding and control of the processing of materials involved in artistic casting by microwaves, in order to facilitate this type of energy sources in the thermal processes of dewaxing. Specifically, the behavior of small samples made with commercial refractory coatings on simple wax models was studied. An adaptation and compatibilization of the conventional technique of fused jewelry was designed to validate an integral treatment with this energy alternative. On the one hand, a suitable time/power curve was designed for the initial dewaxing and drying of these pastes, taking into account the dielectric properties of the water present in their confection. On the other hand, a feasible procedure was studied for the development of their burning, through the use of hybrid heating using silicon carbide (SiC-β) as a susceptor. In order to apply a step temperature, a double muffle combining transparent and absorbing materials with the capacity to reach 750°C with MW power of 700w was fabricated. The results obtained intensified the interest in studying a thermal processing for the dewaxing and firing of refractory linings with larger models and more complex shapes oriented to jewelry and small format sculpture.