Study on the Measurement of Surface Energy of Slag Powder with Different Fineness

Slag is an important cement-based cementitious material. The surface energy state of slag powder is closely related to the rheological properties of composite cement-based cementitious materials and the compatibility of chemical additives. According to the basic principle of thin-layer wicking technique, the surface energy state of slag powder with different fineness was studied by measuring the contact angle of different liquids on the surface of slag powder. The results show that the contact angle measurement results with good stability and reproducibility can be obtained by thin-layer wicking method. The diiodomethane, ethylene glycol and H2O as probe solution, the total surface energy of coarse, medium and fine particle size slag powder was 23.63 mN/m, 32.49 mN/m and 34.59 mN/m, respectively. The non-polar component of surface energy of slag powder particles increased with the decrease of particle size, and the polar component increased with the increase of particle size.