| Title |
Research Paper - Pyometallurgy - : Influence of Al Heating on the Melt Cleanliness in RH - OB Process |
| Authors |
정우광(Woo Gwang Jung); 최인섭(In Sup Choi); 허완욱(Wan Wook Huh) |
| Abstract |
The characteristics of the oxygen blowing treatment in RH operation at Pohang Works of POSCO were investigated to understand the influence of Al heating on the melt cleanliness by 300 ton scale field test. The analysis on the composition, size and shape of inclusion during RH-OB Operation has been made for Al killed and Al-Si killed steel. The efficiency of heating by OB treatment was estimated to be 55% in Al-Si killed steel, and in Al killed steel 55% for oxygen blowing under 150 N㎥ and 75% for oxygen blowing above 150 N㎥, respectively. The melt cleanliness was deteriorated during the oxygen blowing treatment in RH-OB operation, however a sufficient circulation of the melt after the OB treatment improved the cleanliness to a similar level of the melts without OB treatment. The addition of CaO based flux is effective to improve the cleanliness in the melt with OB treatment. The difference in the rejected ratio in cold rolled sheet products was not recognized between the products from the heats with OB and those from the heats without OB treatment in RH-OB operation. |