ZHANG Wei , DAI Wenyong , MENG Qian

(Plibrico (Dalian) Industries Co., Ltd., Dalian Liaoning 116600, China)

Abstract: Effect of different particle sizes of andalusite on properties of bauxite based gunning refractory were investigated with bauxite as raw materials, calcium aluminate cement and silica flour as binders. After 24h curing in mould and another 24h curing at 110℃ after demoulding, the specimens were heat treated at 1000℃, 1300℃ and 1500℃ for 3h, respectively. The permanent linear change, bulk density, modulus of rupture and cold crushing strength, thermal expansion coefficient,abrasion resistance and thermal shock resistance were examined. The results show that big particle size of andalusite cannot offset the shrinkage of bauxite based gunning refractory after high temperature treatment. The bulk density of bauxite based gunning refractory increases with the increasing of the particle size of andalusite. Different particle sizes of andalusite cannot change the strength of bauxite based gunning refractory treated at a medium temperature, big particle size of andalusite can increase the strength of bauxite based gunning refractory treated at a high temperature. The abrasion resistance of bauxite based gunning refractory is improved with the increasing of the particle size of andalusite. Small particle size of andalusite can improve the thermal shock resistance of bauxite based gunning refractory.

Key words: andalusite; particle size; heat treatment temperature; strength; abrasion resistance; thermal shock resistance