Precise Method for Testing Cooling Curve and Eutectic Expansion Curve of Ductile Cast Iron in Front of Furnace

doi:10.3901/JME.2016.06.065

Abstract

Abstract: In order to realize rapid prediction of nodularization effectiveness and iron liquid characteristic for ductile cast iron in front of furnace, a novel experimental setup is designed for combined testing cooling and eutectic expansion linear displacement dual curves. This setup mainly consists of several components, including a cylindrical dry sand cup, a vertically located thermocouple, an expanding rod and a linear displacement sensor connected with the expanding rod. When pouring iron liquid into the sand cup, both the thermal and the diametric expansion/contraction linear displacement curves can be recorded simultaneously for the testing sample during solidifying process by the thermocouple and the linear displacement sensor, respectively. Additionally, the measurement procedure theory in solidification with respect to the new designed setup, as well as the calibration method for measurement offset caused by the expanding rod’s thermal expansion/contraction effect are analyzed. The experimental results measured in foundry plant show that both the cooling and the diametric dimension change curves during solidification for iron liquid sample are accurately registered on line. The new setup can be used for not only nodularity prediction of the nodularization and inoculation effectiveness, but also precipitation kinetics analysis of the graphite during ductile cast iron solidification.

Key words: combined evaluation, ductile cast iron, iron liquid characteristic, nodularization effectiveness, thermal-eutectic expansion dual curves

CLC Number:

TG143

XU Zhenyu, LI Dayong, MA Xuliang, SHI Dequan, WANG Yanfeng. Precise Method for Testing Cooling Curve and Eutectic Expansion Curve of Ductile Cast Iron in Front of Furnace[J]. Journal of Mechanical Engineering, 2016, 52(6): 65-71.

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