Determination of Moisture Content in Synthetic Moulding Sand on the Grounds of Relative Permittivity Measurement

Abstract

The presented research was aimed at searching for an exact and effective method of determining moisture content in traditional moulding sands. By measuring resonance frequency and quality factor of a waveguide resonance cavity, relative permittivity was determined for different synthetic moulding sands. Analysis of the presented results confirms a linear relation between relative permittivity values and moisture content values in the selected traditional moulding sands. The obtained linear relationship can be used as a reference characteristic for evaluation of humidity of moulding sand.

Nondestructive, Microwave Testing of Compression Strength and Moisture Content of Green Molding Sands

“…In article [22], the influence of the microwave frequency in the range 0.1 to 10 GHz has been proven in real and imaginary part of the permittivity of dry silica sand. Many research has shown that knowledge of complex relative permittivity, depending on the physical, chemical or technological factors chosen, allows for rapid and non-destructive determination of the moisture content of the materials containing sand [23][24][25]. Concrete examining have shown that the increase in permittivity has resulted in a decrease in compression strength [26].…”