| The effects of Zr, Ca and Ce on the rate of first stage graphitization, nucleation and growth of graphite particles in nodular cast iron were studied. Activation energies of nucleation and growth were measured and their interrelation was discussed. The activation energies of nucleation and growth of graphite were ranged from 22,000 to 35,000 ㎈/㏖., from 25,000 to 35,000 ㎈/㏖, depending on the nodulizing elements, respectively. The effects on graphitization were as follows. ① The graphitization of Zr-treated cast iron was accelerated by both nucleation and growth of graphite. ② The graphitization of Ca-treated cast iron was accelerated by growth of graphite than nucleation of graphite. ③ The graphitization of Ce-treated cast iron was accelerated by nucleation of graphite than growth of graphite. |
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