Young’s modulus of illitic clay and CaCO3 mixtures during thermal treatment up to 1100 °C

Abstract

The dynamic Young’s modulus of samples, made from a mixture of illitic clay and laboratory grade CaCO3 with 6% addition of 3% solution of polyvinyl alcohol in anorthite stoichiometry is studied. The samples with different CaCO3 contents, namely 17.6%, 21.6%, and 25.6% are made by dry pressing. The measurements of the dimensions, mass, and resonance frequency of the samples are performed for the determination of the dynamic Young’s modulus in the temperature interval from 25 °C to 1100 °C. The influence of the amount of CaCO3 on the Young’s modulus of the samples is investigated. During the firing of the studied samples, the values of Young’s modulus increase due to the liberation of physically bound water (up to 250 °C) and sintering (above 850 °C). The values of Young’s modulus after a firing reach 16.7 – 18.4 GPa, which is about 6 – 9 times higher as the values for the raw samples.