In situ monitoring of used-sand regeneration in foundries by impedance spectroscopy

Abstract. This work deals with the impedimetric monitoring of used-sand regeneration in foundry industry. During used sand, a quartz sand similar to new is produced from already molding and core which especially serves produce cores. We explore whether progress can be assessed situ based on measured impedance spectra their features. The impedances plate capacitors filled different typical mixtures, consisting coal dust, bentonite, were repeatedly frequency range 500 Hz 1 MHz. reproducibility measurements proved sufficient for practical applications. mean plotted Nyquist diagrams. From these plots, systematic impedance–composition correlations could determined two three component systems. Conclusions about state drawn curves by introducing various These median, mean, standard deviation frequency-dependent resistance reactance. With indicators, it was then possible establish one-to-one relations between material composition materials measurement. In field regenerated sands, this observation confirmed, observed basis impedimetrically characteristic data.