Abstract
Three self-hardening organic binders, low-nitrogen furan, oil-urethane and phenol-urethane were tested. Test apparatuses were developed to measure hot surface stability and hot compressive strength. The furan binder shows higher hot strength at 600°C than the urethane binders because of the level of carbon precursor generating after decomposition of the binder. When the temperature of the mold surface is raised to 1,000°C, the urethane binders give higher hot strength than the furan binder. This fact can be explained by the adhesive force of carbon precursor to the sand.
