摘要
Three different castables were prepared as steel-ladle purging-plug refractory materials: corundum-based low-cement castable (C-LCC), corundum-spinel-based low-cement castable (C-S-LCC), and no-cement corundum-spinel castable (C-S-NCC) (hydratable alu- mina p-A1203 bonded). The properties of these castables were characterized with regard to water demand/flow ability, cold crushing strength (CCS), cold modulus of rupture (CMoR), permanent linear change (PLC), apparent porosity, and hot modulus of rupture (HMoR). The re- sults show the CCS/CMoR and HMoR of C-LCC and C-S-LCC are greater than those of the castable C-S-NCC. According to the micro- structure analysis, the sintering effect and the bonding type of the matrix material differ among the three castables. The calcium hexaluminate (CA6) phase in the matrix of C-LCC enhances the cold and hot mechanical strengths. In the case of C-S-LCC, the CA6 and 2CaO·2MgO·14A12O3(C2MEA14) ternary phases generated from the matrix can greatly increase the cold and hot mechanical strengths. In the case of the no-cement castable, sintering becomes difficult, resulting in a lower mechanical strength.
Three different castables were prepared as steel-ladle purging-plug refractory materials: corundum-based low-cement castable (C-LCC), corundum-spinel-based low-cement castable (C-S-LCC), and no-cement corundum-spinel castable (C-S-NCC) (hydratable alu- mina p-A1203 bonded). The properties of these castables were characterized with regard to water demand/flow ability, cold crushing strength (CCS), cold modulus of rupture (CMoR), permanent linear change (PLC), apparent porosity, and hot modulus of rupture (HMoR). The re- sults show the CCS/CMoR and HMoR of C-LCC and C-S-LCC are greater than those of the castable C-S-NCC. According to the micro- structure analysis, the sintering effect and the bonding type of the matrix material differ among the three castables. The calcium hexaluminate (CA6) phase in the matrix of C-LCC enhances the cold and hot mechanical strengths. In the case of C-S-LCC, the CA6 and 2CaO·2MgO·14A12O3(C2MEA14) ternary phases generated from the matrix can greatly increase the cold and hot mechanical strengths. In the case of the no-cement castable, sintering becomes difficult, resulting in a lower mechanical strength.