大鋼胚極低碳鋼氣孔改善

Eliminating of Blow Hole In Bloom for Ultra Low Carbon Steel

陳培倉(Pei-Tsang Chen) ； 馮復安(Fu-An Feng) ； 洪正雄(Cheng-Hsiung Hung) ； 周聖志(Sun-Ju Chou)

《鑛冶：中國鑛冶工程學會會刊》 42卷2期 (1998/06) Pp. 63-72

https://doi.org/10.30069/MM.199806_42(2).0008

摘要

大鋼胚連鑄過程中，由於氣泡或隨附在上浮氣泡內之介在物易被凝殼捕捉。尤其極低碳鋼（C≦150ppm）因模振痕所引發之爪狀凝固組織特別發達，及其溶鋼黏度較大，氣泡上浮阻力大等特性，使表面及次表面品質惡化。本文藉由轉爐吹止碳提昇、盛鋼桶爐渣脫氧等，進行鋼液氧含量控制及爐渣氧化活性降低，以改善鋼液清淨度；在連鑄上，控制吹入模內氬氣量以抑制氣泡過量生成，使極低碳鋼之氣孔獲得明顯改善，而有效提昇小鋼胚研磨工場產能。

關鍵字

極低碳鋼 ； 爪狀凝固組織 ； 模振痕 ； 吹止碳 ； 盛鋼桶

並列摘要

Gas bubbles or inclusions which may agglomerated around rising bubbles are easily entrapped in solidifying shell during bloom continuous casting. Especially for the ultral low carbon (C≦150ppm) steel, which hook-like structure beneath the oscillation mark is more dominant and viscosity of molten steel is relative high, will dampen the buoyancy of gas bubbles and consequently deteriorate the quality of surface and / or subsurface due to blow hole defects. This paper presents the countermeasures to improve the aforementioned problem which include: increasing blowing down carbon of BOF and deoxidizing of ladle slag in order to control oxygen content and cleanness in steel; in addition, adjusting the amount of blowing argon in tundish nozzle to reduce gas bubbles. Thus the productivity of billet grinding mill is certainly promoted.

並列關鍵字

ultra low carbon steel ； hook-like structure ； oscillation mark ； blowing down carbon ； ladle