Preparation and application of MgO/nano MgAl2O4 core-shell aggregates with improved hydration and thermal shock resistance

MgO/nano MgAl 2 O 4 core-shell aggregates were prepared using nano-Al 2 O 3 suspension and MgO aggregates by vacuum impregnation method and then heat treated. The MgO/nano MgAl 2 O 4 core-shell aggregates possess excellent hydration resistance and thermal shock resistance (TSR), which are attributed to the in-situ formed MgAl 2 O 4 reducing the contacting area between MgO and water as well as the reduced pore and pore size. The pinning effect of nano-MgAl 2 O 4 and thermal mismatch between MgO and MgAl 2 O 4 contribute to improving TSR of aggregates. The TSR and hot modulus of ruputure were enhanced when the prepared MgO/nano MgAl 2 O 4 core-shell aggregates were introduced into MgO–C slide plate.