Archimedes revisited: computer assisted micro-volumetric modification of the liquid displacement method for porosity measurement of highly porous light materials

Precise and accurate porosity measurement is essential for characterization of porous materials. Considering Archimedes' principle based liquid displacement methods of measuring porosity we have developed an excellent modified micro-volumetric method of porosity measurement. Changes in the liquid level in a glass pipette after immersing and also removing the porous sample were recorded by using a digital camera and analysed by ImageJ (R) software. Results of porosity measurement through a micro-volumetric method were compared with micro-CT results. Bland-Altman analysis showed a much higher precision and accuracy for our micro-volumetric method (bias = -0.023, Cl: ] -0.459, 0.413[, SD = 1.96 O') compared to the micro-CT method (bias = 6.075, Cl: ] -20.993, 33.142[, SD = 1.96 O'). Our highly precise and accurate micro-volumetric method of porosity measurement is particularly applicable to small ultra-light highly porous materials.