Autores:Luján,R.C., Conesa,I.P. Pérez Sánchez,M.J.

This study evaluates three mixtures of susceptor materials (Graphite + Fe₃O₄, Fe₃O₄ + SiC, Fe₃O₄ + TiO₂) used in the microwave (MW) dewaxing process for ceramic shell casting moulds. This innovative process in artistic casting employs volumetric and localised heating to efficiently remove wax from ceramic shell moulds, significantly reducing processing time and energy consumption.

However, physicochemical alterations in the substrates during heat treatment can impact their stability and efficiency.To address this, the microstructure and composition of susceptors were characterised before and after heat treatment using advanced techniques such as Polarised Light Optical Microscopy (PLOM), Scanning Electron Microscopy/Energy Dispersive X-ray Spectrometry (SEM/EDX), and X-ray Diffraction (XRD). Plate specimens and solid powder scrapings were analysed, providing detailed comparisons of structural and compositional changes across the susceptor mixtures.

The results revealed significant differences in the stability of the evaluated mixtures, with one mixture demonstrating minimal structural alteration and higher resistance to the required dewaxing temperatures. These findings offer critical insights into selecting optimal materials for the microwave dewaxing technique, contributing to more efficient and sustainable processes in artistic casting and related industrial applications.

DOI: https://doi.org/10.1016/j.ceramint.2025.07.246

Autores:Cavero-Luján,R., Pérez-Conesa,I., Acosta-Hernández,F.F., Laz-Pavón,M.M.

The dewaxing process in the artistic lost wax casting technique faces significant problems when using the conventional gas-fired combustion method. This approach generates gas emissions, operational risks and limited material recovery, which underlines the need to explore more sustainable and efficient alternatives. In this study, a comparative analysis is made between the conventional method and an innovative microwave (MW) based technique, evaluating variables such as processing time, temperatures reached, gas emissions, wax recovery and the properties of the recycled wax by X-ray diffraction. The results show that the use of microwaves reduces the processing time by 73 %, while maintaining temperatures below 100 °C. This avoids pyrolysis and combustion of the wax, achieving a 91 % recovery of the material compared to 16 % using the conventional method. In addition, the microwave process emits only 58.48 g of CO₂ equivalent, compared to 11.2 kg of CO₂ equivalent generated by the traditional method, reducing CO2 emissions by 99.48 %. Furthermore, the energy efficiency of the microwave reduces energy costs by 99.26 %. This study determines that microwave technology is a sustainable and efficient alternative for the dewaxing of ceramic scale moulds in artistic casting. It also opens new possibilities in the industry by offering a cleaner, more cost-effective and environmentally friendly method. Its advantages include increased material recovery efficiency, a significant reduction of the carbon footprint and precise control of the thermal process, positioning it as a promising solution for modernising traditional casting techniques and incorporating this technology into the sector.

DOI: https://doi.org/10.1016/j.rineng.2025.105006

Autores:Alejandro Hernández Pérez, Rut Cavero Luján, Itahisa Pérez Conesa.

Proceedings. 3rd International Congress: Humanities and Knowledge.

Enlace: https://portalciencia.ull.es/documentos/679a81992523672cc6140c4e