Structural aspects of blast furnace slag

Interdependence of structure and viscosity of blast furnace slag is discussed based on the available literature. Emphasis is given to both, bridging tendency and network breaking/modifying tendency of the constituents. It is clearly pointed out that slag viscosity cannot be explained only by depolymerization through an increase in basicity, despite the fact that an increase in basicity of the slag, in general, lowers the viscosity of the slag by a process of generation of discrete anions containing simple chains and/or rings by causing depolymerization of the 3D silicate network.