SiC Generation Mechanism in Photovoltaic Crystal Pulling Waste Graphite Infusion Cylinder

Currently, the photovoltaic industry is playing a huge role and growing rapidly. Carbon etching and silicide deposition are common phenomena in furnaces during photovoltaic crystal pulling processes, both of which shorten the service life of graphite components and pollute silicon-based materials; these processes also generate waste graphite components with SiC. Therefore, studying its generation mechanism can help conserve and reuse graphite components in furnaces. This study investigated took photovoltaic crystal pulling waste graphite infusion cylinders used during photovoltaic crystal pulling with significantly different apparent morphologies as the research object. Through systematic characterization and thermodynamic analysis, we investigated the physical and chemical reactions occurring during the generation of SiC in various regions of a discarded graphite infusion cylinder. We derived the SiC delamination, infiltration, and stacking mechanism to explain the formation of the apparent morphological characteristics of the waste graphite infusion cylinder. The generation mechanism of SiC in graphite infusion cylinders during photovoltaic crystal pulling was described to provide suggestions for prolonging the service life of graphite infusion cylinders and treating waste graphite infusion cylinders.