| Ductile iron is one of the important metal materials in industry, ductile iron isbecoming widely used in the field of production and life, and the quality of ductileiron castings is getting more attention by casting and metallurgical researchers. Thespheroidizing treatment and inoculation are required in the melting process of ductileiron, and inoculation is an important influencing factor for the quality of ductile ironcastings. Therefore, the research of optimized control method for the inoculation ofductile iron has an important significance for the quality control of ductile ironcastings.There is an intensive study of inoculation and the solidification processing formolten metal in this article. The important parameters of alloy associated withinoculation treatment effect is analyzed in cooling process of solidification for themolten metal of ductile iron through the method of thermal analysis, optimizedcontrol system of inoculation is designed combining with the computer measurementand control system. The system is constituted of three units, such as the originalmolten iron smelting unit, the inoculation optimized control unit and the streaminoculation unit. The inoculation optimized control unit with human-computerinteraction interface which has the function of detecting and controlling the state ofmolten iron is the core content of this system. This unit is constituted of three parts,such as computer, measurement and control unit and the thread feeding machine. Themeasurement and control unit is consists of hardware parts such as constant currentsource circuit, the analog input channel, the interface converter, the thermal analysissample cup and the software part such as human-computer interaction interface.Human-computer interaction interface is an executable program which is wrote byMicrosoft Visual Basic6.0, this program is wrote with the function of display thecontent of important element in molten iron and the thermal analysis curves with the characteristic value of temperature which is consists of three units,such as the metallurgical state evaluation of original molten iron unit, the inoculationoptimized control unit and the stream inoculation unit. History view function, addingalloy parameters function, detection report generation function, the manual controlfunction for the thread feeding machineand the stream inoculation device.Optimized control system of inoculation is used to the application experiment ofthe production process for the different grades of ductile iron. The experimentalresults show that, the metallurgical state of original molten iron after optimalregulation through the optimized control system of inoculation is suitable for casting,the inoculation effect is improved, the amount of graphite nodule is increased, thecrystalline grain of casting become small, the mechanical property of casting isimprove, the rejection rate is reduced. |
