抄録
The effects of carbon and silica contained in the submerged entry nozzles （SEN） on alumina buildup were investigated． Both were shown to be harmful to alumina deposition．A carbon－free high-alumina SEN was developed and successfully used in actual continous casters．The mechanism of excellent alumina buildup resistance are disscussed as follows：
1）Preventiion of alumina near molten steel ／ nozzle interface caused by the oxidation of alumina in steel by CO and SiO gas which evolves from reactions in silica and carbon containing nozzle refractory materiats．
2）Suppression of concentration gradient of elements such as Si and C in the interface layer between nozzle and molten steel，which can become a driving force of attraction of alumina particles dispersed in molten steel．
https://ror.org/016vzmc05 
