厚板用扁鋼胚之品質改善成效

Improvement of Slab Quality for Heavy Plate

謝宏志(H.C. Hsieh) ； 林冠儒(K.L. Lin) ； 林宏達(H.T. Lin) ； 葉東發(T.F. Yeh)

《鑛冶：中國鑛冶工程學會會刊》 48卷4期 (2004/12) Pp. 89-95

https://doi.org/10.30069/MM.200412_48(4).0007

摘要

鋼板的T/2韌性不合和Z向斷面收縮率不足等機械性質的缺陷，是厚板UT檢驗不合格的主要問題，相對應於鋼胚則是鑄胚的中心偏析和中心孔洞等缺陷所造成。在連鑄機澆鑄的製程，曾經進行改善鑄機噴水的均勻性、先凸後壓試驗、低過熱度澆鑄和強噴水試驗，結果低過熱度澆鑄的效果最佳。目前厚板鋼種的澆鑄製程已訂出合適的標準，未來將朝此目標而努力。

關鍵字

厚板 ； 偏析 ； 孔洞 ； 先凸後壓

並列摘要

Insufficient toughness and low reduction ratio at the center of heavy plate along thickness direction are two main defects in the UT (ultrasonic testing) results. That the defects were caused by centerline segregation and porosities at the center of thickness direction of continuously cast slabs have been confirmed. Several countermeasures, for example uniform distribution of spray pattern, intentional bulging and soft reduction, low superheat casting and increase of specific water ratio etc., were made to solve the above-mentioned problems and consequently quality cast slabs were produced. It was concluded that the low superheat (below 12°C) casting is the most effective measure to improve the quality of heavy plate steel. At present, a standard practice of continuous casting process for heavy plate steel was established.

並列關鍵字

Heavy plate ； Segregation ； Porosities ； Intentional bulging and soft reduction