In-situ generation of silicon carbide whisker to enhance service performance of silicon carbide reticulated porous filter using a replica template method and novel carbon-silicon microspheres

Abstract

Silicon carbide reticulated porous filters are widely used in steel and alloy smelting industries. However, the hollow voids and microcracks in the ceramic skeletons, caused by the burnout of polymer templates, negatively impact the strength, thermal shock resistance, and corrosion resistance of the filters. In this study, the replica template method was employed with slurries containing novel carbon-silicon microspheres to reconstruct the microstructure of the silicon carbide skeleton and enhance the performance of the filters. The incorporation of carbon-silicon microspheres significantly improved the flowability and structural reconstruction ability of the slurry, resulting in a more homogeneous coating layer within the template. After sintering at 1550°C, silicon carbide whiskers were in-situ generated within the hollow voids, microcracks, and on the surface of the silicon carbide skeleton, thereby improving compressive strength and thermal shock resistance. Additionally, the poor wettability between the sample and molten copper enhances the fluidity of the copper solution within the filter, effectively preventing it from adhering to the ceramic filter. This reduces the risk of blockage and minimizes the potential for corrosion of the ceramic filter by the molten copper.