In graphitic steel containing Si, the carbide phase is unstable because of the high Si content of the steel and consequently it may easily decompose by heat treatment, but when the steel contains other elements, the graphitization characteristics may be expected to change. Therefore in this report, the experiments were carried out on forgeability, the graphitization, the change of hardness and the micro-structure of graphitic steel (1.3∼1.5%C, 1.5%Si) specimens containing 0.2∼1.0%Ti, 0.2∼1.0%V and 0.003∼0.1%B respectively by graphitization annealing at elevated temperature. With increasing Ti and V the forgeability of these steels rise and the power of graphitization of Ti is slightly negative and that of V strongly negative. While by increasing B the forgeability of the steel becomes poor, and the amount of graphite decreases. As above, the limit of alloying composition in graphitic steel containing 1.5%C and 1.5%Si is determined as within 1%Ti, 0.5%V and addition of B is unnecessary.
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