The properties of the materials used for making models of sodium silicate bonded sand core curing by microwave energy are suggested. The absorbency and penetrability for microwave energy of polymer and ceramics are measured and analyzed. Polymer and ceramics can be used for making models of sodium silicate bonded sand cores curing by microwave energy. The merits of polymer are its high strain, good tenacity and easy making. The merits of ceramics are its excellent heat-proof and abrasion-proof.