In order to further improve the strength and the thermal shock resistance of Al_(2)O_(3)-C materials for steel ladle slide gates,the effects of four kinds of alumina micropowders(unimodal activated alumina micropowder...In order to further improve the strength and the thermal shock resistance of Al_(2)O_(3)-C materials for steel ladle slide gates,the effects of four kinds of alumina micropowders(unimodal activated alumina micropowder 07RAL,unimodal activated alumina micropowder 15RA,bimodal activated alumina micropowder 22RABL,and calcined alumina micropowder 40CA)on the density,the strength and the thermal shock resistance of Al_(2)O_(3)-C materials were studied.The results show that the density,the strength and the thermal shock resistance of Al_(2)O_(3)-C materials can be improved with the introduction of activated alumina micropowders.Among them,the specimen with bimodal activated alumina micropowder shows the best comprehensive performance,especially the hot modulus of rupture.Its actual application results in steel mills show that the average service life of the Al_(2)O_(3)-C slide plates prolongs,and the problems of cast hole reaming,plate oxidation,roughening and cracking during the use of slide plates are obviously improved.展开更多
To enhance the performance,reactive MgO-bonded corundum-spinel castables were prepared using tabular corundum,reactive alumina,reactive MgO,and aluminum lactate as raw materials.The influence of the reactive alumina a...To enhance the performance,reactive MgO-bonded corundum-spinel castables were prepared using tabular corundum,reactive alumina,reactive MgO,and aluminum lactate as raw materials.The influence of the reactive alumina addition(0,8%,13%,and 18%,by mass)on the microstructure,phase composition,physical properties,as well as the resistance to slag corrosion and penetration of the castables was investigated.The results show that:(1)the reactive alumina promotes the sintering of the reactive MgO-bonded corundum-spinel castables,enhancing the bonding between aggregates and matrix,thus densifying the microstructure;(2)with the increase of the reactive alumina,the volume stability of the samples increases,the apparent porosity decreases,the bulk density increases,and the cold modulus of rupture and cold compressive strength as well as the slag resistance are improved;(3)the reactive MgO-bonded corundum-spinel castable with 18%reactive alumina shows optimal comprehensive performance,with the bulk density of 3.05 g·cm^(-3),apparent porosity of 18.5%,permanent linear change rate after heating of 0.31%,cold modulus of rupture of 13.5 MPa and cold compressive strengths of 73.8 MPa,as well as the best slag resistance.However,considering particle size distribution and raw material costs,there is no need to further increase the reactive alumina addition.展开更多
文摘In order to further improve the strength and the thermal shock resistance of Al_(2)O_(3)-C materials for steel ladle slide gates,the effects of four kinds of alumina micropowders(unimodal activated alumina micropowder 07RAL,unimodal activated alumina micropowder 15RA,bimodal activated alumina micropowder 22RABL,and calcined alumina micropowder 40CA)on the density,the strength and the thermal shock resistance of Al_(2)O_(3)-C materials were studied.The results show that the density,the strength and the thermal shock resistance of Al_(2)O_(3)-C materials can be improved with the introduction of activated alumina micropowders.Among them,the specimen with bimodal activated alumina micropowder shows the best comprehensive performance,especially the hot modulus of rupture.Its actual application results in steel mills show that the average service life of the Al_(2)O_(3)-C slide plates prolongs,and the problems of cast hole reaming,plate oxidation,roughening and cracking during the use of slide plates are obviously improved.
基金Joint Founds of R&D Program of Henan Province(222301420034)Collaborative Innovation Major Special Project of Zhengzhou(No.20XTZX2025)for the financial support.
文摘To enhance the performance,reactive MgO-bonded corundum-spinel castables were prepared using tabular corundum,reactive alumina,reactive MgO,and aluminum lactate as raw materials.The influence of the reactive alumina addition(0,8%,13%,and 18%,by mass)on the microstructure,phase composition,physical properties,as well as the resistance to slag corrosion and penetration of the castables was investigated.The results show that:(1)the reactive alumina promotes the sintering of the reactive MgO-bonded corundum-spinel castables,enhancing the bonding between aggregates and matrix,thus densifying the microstructure;(2)with the increase of the reactive alumina,the volume stability of the samples increases,the apparent porosity decreases,the bulk density increases,and the cold modulus of rupture and cold compressive strength as well as the slag resistance are improved;(3)the reactive MgO-bonded corundum-spinel castable with 18%reactive alumina shows optimal comprehensive performance,with the bulk density of 3.05 g·cm^(-3),apparent porosity of 18.5%,permanent linear change rate after heating of 0.31%,cold modulus of rupture of 13.5 MPa and cold compressive strengths of 73.8 MPa,as well as the best slag resistance.However,considering particle size distribution and raw material costs,there is no need to further increase the reactive alumina addition.
