This work explored the way to improve hot modulus q/' rupture (HMOR) and refractoriness under load (RUL) by adding mild-calcined coal gangue (MCG) in Al2O3 -SiO2 ultra low cement (ULC) castables, making use o...This work explored the way to improve hot modulus q/' rupture (HMOR) and refractoriness under load (RUL) by adding mild-calcined coal gangue (MCG) in Al2O3 -SiO2 ultra low cement (ULC) castables, making use of the in-situ effect of the MCG during heating-up. The influence of respective additions of 5%, 10% and 1.5% of the MCG powders calcined at 700℃ was investigated on HMOR at 1400 ℃ and RUL of the castables. With increased addition of the MCG, HMOR and RUL become significantly enhanced. At 10% of the MCG addition, HMOR reaches 3 MPa, as compared to 0. 3 MPa in the case of no MCG addition. RUL of the specimens dried at 110 ℃for 24 h can be increased by some 270 ℃ with 10% of the MCG addition. RUL 0.11 the specimens preheated at 1 500℃ for 3 h maintains the growth trend with the MCG addition increasing. The microstructure of the heated castable samples was investigated by means of SEM. The in-situ formed needle-like and interlaced mullite in the matrix is contributive to the tmprovement.展开更多
A1203-SiC-C iron trough castables were prepared using high alumina bauxite clinker GL-90 ( 〉 1 mm ) or homogenized bauxite GL-88 to replace the traditional brown corundum aggregates ( 〉 1 mm ) to reduce the cost...A1203-SiC-C iron trough castables were prepared using high alumina bauxite clinker GL-90 ( 〉 1 mm ) or homogenized bauxite GL-88 to replace the traditional brown corundum aggregates ( 〉 1 mm ) to reduce the cost of iron trough castables. Effects of the two bauxite aggregates on properties of iron trough eastables were investigated. The results show that the two kinds of bauxite affect flowability, bulk density, strength and slag corrosion resistance of trough castables differently. Compared with homogenized bauxite, high alumina bauxite clinker is more suitable to substitute brown corundum. The castables prepared from the bauxite clinker have similar performances with those prepared from brown corundum, especially used in medium or small blast furnaces with weak thermal impact and lower temperature hot metal. However, in large blast furnaces with severe thermal impact and high temperature hot metal, the performances of the two castables are significantly different. So it is suggested to use the brown corundum based castables in the front gyral zone of the slag skimmer.展开更多
文摘This work explored the way to improve hot modulus q/' rupture (HMOR) and refractoriness under load (RUL) by adding mild-calcined coal gangue (MCG) in Al2O3 -SiO2 ultra low cement (ULC) castables, making use of the in-situ effect of the MCG during heating-up. The influence of respective additions of 5%, 10% and 1.5% of the MCG powders calcined at 700℃ was investigated on HMOR at 1400 ℃ and RUL of the castables. With increased addition of the MCG, HMOR and RUL become significantly enhanced. At 10% of the MCG addition, HMOR reaches 3 MPa, as compared to 0. 3 MPa in the case of no MCG addition. RUL of the specimens dried at 110 ℃for 24 h can be increased by some 270 ℃ with 10% of the MCG addition. RUL 0.11 the specimens preheated at 1 500℃ for 3 h maintains the growth trend with the MCG addition increasing. The microstructure of the heated castable samples was investigated by means of SEM. The in-situ formed needle-like and interlaced mullite in the matrix is contributive to the tmprovement.
文摘A1203-SiC-C iron trough castables were prepared using high alumina bauxite clinker GL-90 ( 〉 1 mm ) or homogenized bauxite GL-88 to replace the traditional brown corundum aggregates ( 〉 1 mm ) to reduce the cost of iron trough castables. Effects of the two bauxite aggregates on properties of iron trough eastables were investigated. The results show that the two kinds of bauxite affect flowability, bulk density, strength and slag corrosion resistance of trough castables differently. Compared with homogenized bauxite, high alumina bauxite clinker is more suitable to substitute brown corundum. The castables prepared from the bauxite clinker have similar performances with those prepared from brown corundum, especially used in medium or small blast furnaces with weak thermal impact and lower temperature hot metal. However, in large blast furnaces with severe thermal impact and high temperature hot metal, the performances of the two castables are significantly different. So it is suggested to use the brown corundum based castables in the front gyral zone of the slag skimmer.