HIGH TEMPERATURE CRUSHING STRENGTH OF VARIOUS IRON ORE PELLETS.

The high-temperature crushing strength of iron ore pellets was measured in air atmosphere in the range from 600 to 100 degree C for eight types of self-fluxing pellets with basicities up to 2. 54 and slag contents up to 16. 3%, three kinds of acid pellets, and two kinds of pure hematite pellets with or without calcium silicate. The strength generally decreases as the tempeerature rises. However, the pellets containing silicate slags as major bonding phases showed a strength recovery, depending on the nature of the silicates. The temperature at which such strength recovery takes place varies with the composition of the silicate slag. An increase in the slag content enhanced the room temperature strength but it does not influence much the high-temperature strength.