Study On The System Of Rapid Evaluating Ductile Iron Spheroidization Effect In Front Of The Furnace

In the past50years, ductile iron has played a significant role in the humancivilization and social progress. Although China is a big country of production ofductile iron, the casting quality is still not stable enough, so to evaluate ductile ironquality in front of furnace is very significant for stable production of ductile iron.A rapid system of evaluating ductile iron spheroidization treatment in ladle fortesting the cooling curve and eutectic expansion curve of liquid iron quickly andaccurately is designed in the paper. The rapid evaluation system which is based oneutectic expansion-thermal analysis method and computer measurement and controltechnology includes two parts of rapid evaluation hardware system unit and rapidevaluation software system unit. The rapid evaluation hardware system unit mainlyconsists of conjoint analysis sampling unit and data acquisition and processing unit.The conjoint analysis sampling unit for sampling in liquid iron is mainly composedof thermal analysis sample cup, displacement guide rod, displacement sensor, etc.This conjoint analysis sampler is different from previous eutectic expansion sampler,the expansion of melt sample is fully realized by the single end of displacementguide rod. Data acquisition and processing unit are acquired by Adam modules, andit is used to acquire and process the temperature signal and displacement signal fromsampler and communicate with computer. Software system of rapid evaluation unitdesigned by VB6.0, can acquire and save the sample solidification process data,history view function, automatically distinguish the characteristic value in thecooling curve and eutectic expansion curve, show the evaluation results by the modelof cognition.In this paper the design processes of every unit are introduced in detail and thecooling curve and eutectic expansion curve of QT550-7measured by the rapidevaluation system are presented. The effect of spheroidization treatment of eachcomponent QT550-7were evaluated using the rapid evaluation system, the resultswere consistent with the traditional metallographic observations.