Pore evolution and slag resistance of corundum castables with nano zirconia addition

The effect of nano-zirconia addition on the microstructure and properties of corundum castables was studied using corundum, kyanite, alumina powder, gel powder, and nano-ZrO 2 as raw materials. The results showed that adding 1.2(wt)% nano-ZrO 2 could reduce the median pore diameter of the castables from 480 to 200 nm at 110 °C. After the castables were heated at 1100 °C, the cold modulus of rupture increased by 29.95%, to 24.71 MPa, and the cold compressive strength increased by 50.32%, to 116.37 MPa. The hot modulus of rupture increased by 114.95%, to 3.59 MPa after being treatment at 1500 °C, the high surface energy of nano-ZrO 2 can increase the interface energy and bonding strength between adjacent particles.