Siliconizing effect on cast iron by amorphous/crystalline silica contained in rice husk

Abstract

A coal coke and carburizing material has used in the casting process, environmentally friendly casting is required. We need shift from fossil resource to bioenergy. In the domestic, the rice husk is discarding about 200,000 ton per year. However, contains about 14wt.% by the amorphously SiO₂ (silica). As a well-known fact, when introducing rice husks as a silica material in the casting process, it has been confirmed that a part of the contained silicon is silicified into cast iron. A silica alloy in the casting process is contained as a crystalline material. In this study, Biocoke provide two type by mix crystalline silica reagent and amorphous silica reagent in the cedar base material (does not exist silicon). We found that the silicon content in the melted casting has increase in both mixed crystalline and amorphous Biocoke, and silicon was hardly released into the atmosphere, and to saturate according to elapsed time.