过冷灰铸铁中铌、钼、镍的作用研究

Research of the Effect of Nb.Mo.Ni in Undercooling Gray Irons

研究了微量铌、钼、镍对过冷灰铸铁组织和力学性能的影响。结果表明，三种元素均可使过冷灰铸铁力学性能提高，其中以钼的综合作用最为显著，而钼对硬度影响最大。过冷灰铸铁石墨形态的改变是力学性能提高的主要原因，而钼加入后自由渗碳体的析出导致硬度显著提高。

The effect of Nb.Mo.Ni on the structure and mechanical properties of undercooling gray cast irons isstudied. The results demonstrate that the mechanical properties of the trace elements ,the effect of Nb was remarkable ,but Mo is most effective on hardness . The improvements of graphite morphology was the main reason for the increasingof mechanical properties and the forming of free cementite results in the increasing of hardness when Mo was added.