抄録
The mechanical properties in thick sections and chilling in thin sections of low sulfur spheroidal graphite cast iron were investigated. Chilling could not be eliminated in thin section by Mg addition, but could be eliminated by combining Mg and RE. However, the range of the amount of RE added for eliminating chilling was extremely limited for extremely low sulfur melt. In spheroidal graphite cast iron containing Mg and RE, the high tensile strength of 500 MPa or above in thick sections (φ 30 mm) was obtained without chilling. For the extremely low sulfur cast iron, excellent elongation was obtained.
