Investigations of surface forces between gypsum crystals in electrolytic solutions using microcantilevers

This paper introduces a new approach to the study of the interactions between gypsum faces in electrolytic solutions of calcium sulfate. A systematic study with respect to the orientation of crystals, the concentration of the solution, the type of electrolyte, and the duration time of the contact leads to an improved understanding of both the DLVO theory and the mechanism involved in the development of the ionic correlation force. Using an atomic force microscope, direct local measurement of forces between crystals defines the ideal conditions favorable to the adhesion. The most important factor in crystal coagulation was found to be the effective surface charge of each face.