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根据凝固动力学理论，建立和完善了球墨凝固过程中各阶段组织形成的数学模型。用试验试件进行了验证，并对实际生产球墨铸铁件的球墨数量和大小、珠光体和铁素体数量、硬度等进行了模拟，与定量金相分析结果进行了比较。结果表明模拟结果与分析结果吻合较好，同时，共析模型尚有待进一步改进以更准确地预测珠光体和铁素体数量。研究表明：球墨的形核与生长主要与过冷有关，共析阶段产生的珠光体与铁素体体积分数则由过冷度与球墨个数两者所决定。
According to the theory of solidification kinetics, a mathematical model of tissue formation during the solidification of nodular ink was established and perfected. The test specimens were used for verification. The numbers and sizes of ductile irons, pearlite and ferrite, hardness and so on in actual production of ductile iron were simulated and compared with the results of quantitative metallographic analysis. The results show that the simulation results agree well with the analysis results. At the same time, the eutectoid model needs to be further improved to more accurately predict the amount of pearlite and ferrite. The results show that the nucleation and growth of the nodules are mainly related to the undercooling. The volume fraction of the pearlite and ferrite produced in the eutectoid phase is determined by both the degree of undercooling and the number of nodules.