Magnesia zirconia brick containing 11 wt% zirconia was prepared with magnesia and monoclinic zirconia as starting materials in order to replace the chrome-containing materials for Rtt furnace. The corrosion resistance...Magnesia zirconia brick containing 11 wt% zirconia was prepared with magnesia and monoclinic zirconia as starting materials in order to replace the chrome-containing materials for Rtt furnace. The corrosion resistance of magnesia zirconia brick and fused rebonded magnesia chrome brick (short for magnesia chrome brick) to high, and low basicity slag of RH fitrnace was comparatively researched by rotary slag method and their slag resistance mechanisms were analyzed. The results show that: (1) because the reaction layer containing CaZrO3 forms in magnesia zirconia brick, it has better corrosion resistance to high basicity slag than magnesia chrome brick, however, it has worse corrosion resistance to low basicity slag than magnesia chrome brick; (2) ZrO2 in the magnesia zirconia brick can absorb CaO in the slag, which decrea- ses the basicity of slag and inereases the viscosity of slag, so the degree of slag penetration in magnesia zircon.ia brick decreases ; ( 3 ) there is little zirconia in the slag layer of residual nutgnesia zirconia brick;from working face to original brick layer, the residual magnesia zirconia brick shows three layers: obviotasly deteriorative layer, slightly deteriorative layer, and original brick layer, but the residual magnesia chrome brick only shows two layers : obviously deteriorative layer and original brick layer; the SiO2 content of residual magnesia zirconia brick is the highest in the slightly deteriorative layer, however, the SiO2 content of residual magnesia chrome brick gradually decreases front working face to original brick layer.展开更多
Six kinds of Cr2O3 - Al2 O3 fused grains (the mass percent of Cr203 was 15%, 40%, 50%, 60%, 85% and 99%, respectively ) were prepared using chrome green and Al203 powder as starting materials by electro-fnsion, n...Six kinds of Cr2O3 - Al2 O3 fused grains (the mass percent of Cr203 was 15%, 40%, 50%, 60%, 85% and 99%, respectively ) were prepared using chrome green and Al203 powder as starting materials by electro-fnsion, named as CR15, CR40, CR50, CR60, CR85, and CR99, respectively. The corrosion resistance of the six kinds of Cr2O3- Al2O3.fused grains (4-1 ram) was studied using rotary slag corrosion method. The results show that: ( 1 ) the corrosion resistance of the fused grains increases with the Cr203 content and the grain size increasing; (2)the grains of CR99 and CR85 with higher Cr2O3 content are corroded at the slag surJace layer, because FeO and Al2O3. in the slag corrode the grains ; FeO reacts with Cr2O3 in the aggregates.forming (Fe, Cr )3O4 ,spinel firstly, and the spinel reacts with other phases forming composite spinel; when FeO is fidly consumed, Al2 O3 penetrated into the grains reacts with Cr2O3 Jorming Al2O3 - Cr2O3 solid solution on the grains surface; (3) for CR60, the corrosion exists both in the slag surface layer and in the penetration layer; in the penetration layer, CaO and SiO2 react with Al2O3 in Al2O3 - Cr2O3 solid solution forming anorthite , gehlenite ,and glass phase; the grains of CR50, CR40 and CRI5 have the same corrosion mechanism with CR60 in the penetration layer.展开更多
文摘Magnesia zirconia brick containing 11 wt% zirconia was prepared with magnesia and monoclinic zirconia as starting materials in order to replace the chrome-containing materials for Rtt furnace. The corrosion resistance of magnesia zirconia brick and fused rebonded magnesia chrome brick (short for magnesia chrome brick) to high, and low basicity slag of RH fitrnace was comparatively researched by rotary slag method and their slag resistance mechanisms were analyzed. The results show that: (1) because the reaction layer containing CaZrO3 forms in magnesia zirconia brick, it has better corrosion resistance to high basicity slag than magnesia chrome brick, however, it has worse corrosion resistance to low basicity slag than magnesia chrome brick; (2) ZrO2 in the magnesia zirconia brick can absorb CaO in the slag, which decrea- ses the basicity of slag and inereases the viscosity of slag, so the degree of slag penetration in magnesia zircon.ia brick decreases ; ( 3 ) there is little zirconia in the slag layer of residual nutgnesia zirconia brick;from working face to original brick layer, the residual magnesia zirconia brick shows three layers: obviotasly deteriorative layer, slightly deteriorative layer, and original brick layer, but the residual magnesia chrome brick only shows two layers : obviously deteriorative layer and original brick layer; the SiO2 content of residual magnesia zirconia brick is the highest in the slightly deteriorative layer, however, the SiO2 content of residual magnesia chrome brick gradually decreases front working face to original brick layer.
文摘Six kinds of Cr2O3 - Al2 O3 fused grains (the mass percent of Cr203 was 15%, 40%, 50%, 60%, 85% and 99%, respectively ) were prepared using chrome green and Al203 powder as starting materials by electro-fnsion, named as CR15, CR40, CR50, CR60, CR85, and CR99, respectively. The corrosion resistance of the six kinds of Cr2O3- Al2O3.fused grains (4-1 ram) was studied using rotary slag corrosion method. The results show that: ( 1 ) the corrosion resistance of the fused grains increases with the Cr203 content and the grain size increasing; (2)the grains of CR99 and CR85 with higher Cr2O3 content are corroded at the slag surJace layer, because FeO and Al2O3. in the slag corrode the grains ; FeO reacts with Cr2O3 in the aggregates.forming (Fe, Cr )3O4 ,spinel firstly, and the spinel reacts with other phases forming composite spinel; when FeO is fidly consumed, Al2 O3 penetrated into the grains reacts with Cr2O3 Jorming Al2O3 - Cr2O3 solid solution on the grains surface; (3) for CR60, the corrosion exists both in the slag surface layer and in the penetration layer; in the penetration layer, CaO and SiO2 react with Al2O3 in Al2O3 - Cr2O3 solid solution forming anorthite , gehlenite ,and glass phase; the grains of CR50, CR40 and CRI5 have the same corrosion mechanism with CR60 in the penetration layer.