In view of the service failure and low continuous casting production efficiency due to the corrosion of refractories at the slag-line in submerged entry nozzles,a submerged entry nozzle for low-carbon aluminum killed ...In view of the service failure and low continuous casting production efficiency due to the corrosion of refractories at the slag-line in submerged entry nozzles,a submerged entry nozzle for low-carbon aluminum killed steel continuous casting in one steel plant was sampled and taken as the research object to analyze the causes and the mechanism of refractory corrosion at the slag-line.The results show that the core issue of the corrosion and necking of the slag-line materials is that the slag-line material are eroded,dissolved,and reacted by the mold flux gradually.Therefore,it is important to suppress or avoid the contact and reaction between the mold flux and slag-line materials.展开更多
Low cement Al2O3 - SiO2 castables was prepared using super grade bauxite （ w（ Al2O3 ） 〉85% ） as aggregate, brown fused corundum, silicon carbide, Secar 71 CA cement, α-Al2O3 micropowder and microsilica as fine p...Low cement Al2O3 - SiO2 castables was prepared using super grade bauxite （ w（ Al2O3 ） 〉85% ） as aggregate, brown fused corundum, silicon carbide, Secar 71 CA cement, α-Al2O3 micropowder and microsilica as fine powders. The influence of SiC （0, 5 wt%, 10 wt%, and 15 wt% ）on resistance to PbO- rich slag was investigated by static crucible slag test （1 300℃ for 5 h, in air）. The slag corrosion mechanism of the castables was analyzed by means of SEM, EDS and XRD. The results show that the resistance of Al2O3 -SiO2 castables to PbO-rich slag is improved obviously by the addition of SiC. The corrosion mechanism of the PbO-rich slag can be discribed as that PbO in the slag reacts with SiO2 and CaO in Al2O3 - SiO2 castables, forming low-melting compounds （such as PbO · SiO2 and 2PbO · SiO2 ）.展开更多
For the proper use of micropowders in castables,slurries and fired samples were prepared with two kinds of corundumspinel micropowders(D and G).The effects of the solid content and disperser WSM-R1 on the rheological ...For the proper use of micropowders in castables,slurries and fired samples were prepared with two kinds of corundumspinel micropowders(D and G).The effects of the solid content and disperser WSM-R1 on the rheological properties of the slurries were studied.The sintering properties and the slag corrosion resistance of the fired samples were also researched.The results show that:the slurries all show pseudoplastic rheological characteristics.With the same solid content,the slurry with micropowder G has higher initial viscosity than that with micropowder D.Disperser WSM-R1 significantly reduces the initial viscosity of the two slurries and plays a more obvious dispersing effect on the slurry with micropowder G.The fired sample with micropowder G has higher bulk density,lower apparent porosity and better corrosion resistance than that with micropowder D.展开更多
基金the financial support from the National Natural Science Foundation of China(Grant No.52174302,No.51932008 and No.52304347)the Central China Thousand Talents Project(204200510011).
文摘In view of the service failure and low continuous casting production efficiency due to the corrosion of refractories at the slag-line in submerged entry nozzles,a submerged entry nozzle for low-carbon aluminum killed steel continuous casting in one steel plant was sampled and taken as the research object to analyze the causes and the mechanism of refractory corrosion at the slag-line.The results show that the core issue of the corrosion and necking of the slag-line materials is that the slag-line material are eroded,dissolved,and reacted by the mold flux gradually.Therefore,it is important to suppress or avoid the contact and reaction between the mold flux and slag-line materials.
文摘Low cement Al2O3 - SiO2 castables was prepared using super grade bauxite （ w（ Al2O3 ） 〉85% ） as aggregate, brown fused corundum, silicon carbide, Secar 71 CA cement, α-Al2O3 micropowder and microsilica as fine powders. The influence of SiC （0, 5 wt%, 10 wt%, and 15 wt% ）on resistance to PbO- rich slag was investigated by static crucible slag test （1 300℃ for 5 h, in air）. The slag corrosion mechanism of the castables was analyzed by means of SEM, EDS and XRD. The results show that the resistance of Al2O3 -SiO2 castables to PbO-rich slag is improved obviously by the addition of SiC. The corrosion mechanism of the PbO-rich slag can be discribed as that PbO in the slag reacts with SiO2 and CaO in Al2O3 - SiO2 castables, forming low-melting compounds （such as PbO · SiO2 and 2PbO · SiO2 ）.
基金fully funded by National Natural Science Foundation of China and Youth Fund Projects(51802235)
文摘For the proper use of micropowders in castables,slurries and fired samples were prepared with two kinds of corundumspinel micropowders(D and G).The effects of the solid content and disperser WSM-R1 on the rheological properties of the slurries were studied.The sintering properties and the slag corrosion resistance of the fired samples were also researched.The results show that:the slurries all show pseudoplastic rheological characteristics.With the same solid content,the slurry with micropowder G has higher initial viscosity than that with micropowder D.Disperser WSM-R1 significantly reduces the initial viscosity of the two slurries and plays a more obvious dispersing effect on the slurry with micropowder G.The fired sample with micropowder G has higher bulk density,lower apparent porosity and better corrosion resistance than that with micropowder D.
