Nanoscale heterogeneities in a fractured alkali-activated slag binder: A helium ion microscopy analysis

Helium ion microscopy is used to provide new insight into the nano- and microscale morphology of cleaved surfaces of alkali-activated slag (AAS), revealing that AAS contains several types of gel with varying surface morphologies after being subjected to D-drying. It is seen that the bulk C-(N)-A-S-H gel is globular in nature in a silicate-activated slag paste while the gel covering the slag particles is foil-like.