WAVE Series

Electro-acoustic technique for the rapid evaluation of pore size and porosity

No vacuum, no pressurised gasses, no mercury!

Measuring principles

Porosity
The measurement of porosity percentage uses very high frequency conductivity measurements.

Mean Pore Size
The measurement of mean pore size is based on the seismoelectric effect. When an ultrasonic pressure is applied, it causes the so called electrical “double layer” at the interface of the solid surface and liquid, to shear, resulting in a creation of an oscillating current. When double layers overlap the seismoelectric effect is dependent on the pore width.

Zeta Potential of the surface inside the pore structure
Zeta potential measurement uses the same seismoelectric effect. The ultrasound wave causes the highly conductive liquid within the pores to move in relation to the solid surface. This, in turn, causes relative motion of charges that are located in the diffuse layer and on the pores’ surfaces. This is expressed as an oscillating electric current called the Streaming Vibration Current.

Performing the measurement

The sample is fully wetted with a suitable liquid. The choice of liquid depends on the type of sample and the measurement to be performed.
A suitable probe (two probes in case of the mean pore size measurement) is attached to the surface of the sample.
The electronic circuits perform all the necessary functions with the results displayed on a screen within one or two minutes.

Benefits

• A revolutionary new method for a rapid estimation of porosity without the use of pressurised gasses, vacuum pumps or mercury
• With Repeatability of <1% an ideal QC tool
• Real time data capture
• Windows based software
• Results stored in a database with a facility to export to Excel

Read more about pore size distribution and analysis.

For more information contact us.