抄録
First, this paper deals with the graphitization of cast graphitic steels containing 1.0∼1.8%C and 1.5%Si by annealing under several conditions. Second, some mechanical properties of these cast steels graphitized by several heat treatments were measured. As the result of the present study, it has been found that, (1) The time for graphitization at 800∼1000° is decreased by forging of cast specimens. (2) These cast steels containing more than 1.4%C easily graphitize by annealing at 950° for 3 hrs and cooling at the rate of 50°/hr, and then spheroidal graphite is obtained. (3) The highest tensile strength and the elongation of these steel specimens are shown by those containing 1.4∼1.6%C and 1.5%Si.
