Effect of Resin Impregnation on Mechanical Properties of Rice Hull Silica Carbon

New utilization of rice hull, which is one of the agricultural by-products in Japan, is required to use as an industrial resource from a viewpoint of recycling. The rice hull silica carbon (RHS carbon) material is manufactured by mixing and impregnating the rice hull with a phenol resin, and then carbonizing in a nitrogen gas atmosphere at high temperatures. The RHS carbon has the natural porous structure that is originated from the natural structure of the rice hull. Since the RHS carbon has excellent frictional properties, it is expected to use as a friction element in a linear motion slider. However, the mechanical properties of the RHS carbon were dispersed largely, and were strongly affected by the making process. In this study, the authors discussed the effects of the impregnation rates of the phenol resin, and obtained the optimal impregnation rate to achieve the low dispersion in the mechanical properties. Moreover, the effect of the molding method on the mechanical properties was evaluated by some mechanical tests.