封盒退火冷軋鋼捲「條紋積碳」缺陷成因分析與改善

Analysis and Improvement of the Lath Graphite Defect Formed on the Surface of Cold-Rolled and Bath-Annealed Steel Coils

陳宗榮(T.R. Chen) ； 葉聰海(T.H. Yeh)

《鑛冶：中國鑛冶工程學會會刊》 50卷1期 (2006/03) Pp. 48-57

https://doi.org/10.30069/MM.200603_50(1).0006

摘要

「條紋積碳」為BA退火冷軋鋼捲特有的一種表面缺陷，長久以來一直都是此類鋼捲生產時的主要缺陷之一。本文即是針對此一缺陷的成因進行研究，利用退火前、後試片表面分析和觀察的結果，推導出缺陷可能的形成機構，並於實驗室裡加以模擬和驗證，最後並找出關鍵的製程因素來加以改善。研究的結果顯示，熱軋除銹不良所造成的「軋入銹皮」缺陷是冷軋鋼捲BA退火後形成此一缺陷的主因，加強熱軋時的除銹並改以全氫退火的方式進行生產，可以減少軋入銹皮的產生，並降低退火時鋼捲表面的石墨化反應，「條紋積碳」的缺陷可以因此而獲得明顯的改善。

關鍵字

條紋積碳 ； 封盒退火 ； 冷軋鋼捲 ； 軋入銹皮 ； 全氫退火

並列摘要

＂Lath Graphite＂ is one of the major defects that are often formed on the surface of cold-rolled steel coils annealed by the batch annealing (BA) process. In this article, the origin of this defect was studied by analyses of the surfaces of the steel samples before and after annealing. The formation of this defect was also simulated in the laboratory by the controlled annealing conditions. With the help of both analyses and simulations, the key processing parameters that contribute to Formation of this defect were identified. It was found that the ＂roll-in scale＂, due to insufficient de-scaling operation in the hot rolling process, is the origin of this surface defect. Increase of the de-scaling ability in the hot strip mill and use of 100% H_2 atmosphere for the annealing can help to eliminate the roll-in scale and reduce the reaction of graphite formation in the annealing. The problem of ＂Lath Graphite＂ defect formed on the steel surface can be greatly improved accordingly.

並列關鍵字

Lath graphite ； Batch annealing ； Cold-rolled steel coils ； Roll-in scales ； 100% H2 atmosphere annealing