准确、全面评价原铁液的综合冶金质量状态是有效实施球墨铸铁球化孕育处理的基础和保障。基于灰色系统中的关联度理论，研究球墨铸铁原铁液冶金质量状态综合表征参数体系和评价模型的建立方法，并分析所建评价模型的有益效果及应用条件。其步骤主要包括：建立原铁液冶金质量状态综合评价参数体系；构建原铁液冶金质量状态评价灰色关联模型。根据模型计算的关联度综合评价值确定原铁液冶金质量状态等级，并参考各评价参数具体关联系数值，制定冶金状态调整方案。实验室模拟应用结果显示，利用评价参数体系灰色关联度值可以综合评判原铁液的相对冶金质量状态。单个评价参数点的灰色关联系数可表征该参数与该生产条件下最优值的接近程度，并不完全决定最终球化效果。在稳定的生产条件下，评价模型预报球墨铸铁原铁液四个质量等级的准确率可达90%以上。
Accurately and overall evaluating the comprehensive metallurgy status of base iron is the basis and guarantee for effective implementation of nodularization and inoculation treatment in ductile iron production. The establishing method of a comprehensive characterization parameter system and the corresponding evaluation model for the metallurgical status of base iron for ductile iron are studied based on the correlation degree theory in the grey system. Then, the beneficial effects and application conditions are analyzed. The main steps include:Constructing a comprehensive evaluation parameter system; Establishing the grey correlation model for metallurgical status evaluation of the base iron; Determining classification grades of the metallurgical status according to the comprehensive evaluation value calculated form the correlative evaluation model, and the adjustment plan for metallurgical status could be made according to each correlation coefficient value of single evaluation parameter. The simulation application results in laboratory condition show that the grey correlation degree value could be used to effectively evaluate the relative metallurgy quality status of the base iron. A single correlation coefficient value from each evaluation parameter could characterize the close degree to the optimal value of this characteristic parameter in the production conditions, but did not entirely determine the final nodularization effect. Under the condition of stable production, the predictive accuracy of evaluation model for divided "four grades" of base iron quality of ductile iron can reach more than 90%.
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