加鈮抗粗晶鋼之連鑄控制技術建立

The Study of Anti-Grain-Coarsening for Nb Micro-Alloyed Steel in Bloom Continuous Casting Process

蔡德昌(D.C. Tsai) ； 陳正信(J.H. Chen) ； 林暉然(H.J. Lin) ； 郭春億(C.Y. Kuo) ； 林俊男(C.N. Lin)

《鑛冶：中國鑛冶工程學會會刊》 66卷1期 (2022/03) Pp. 57-60

https://doi.org/10.30069/MM.202203_66(1).04

摘要

齒輪、傳動軸等汽機車用鋼通常是採用SCM420、SCr420等低碳合金鋼種以提供本體的韌性，再透過滲碳處理提升表面的耐磨耗性與疲勞壽命。而SCr420加鈮鋼擴量生產後，經常出現晶粒尺寸評估不合，鋼品合格率僅11%，經分析研判晶粒尺寸不合，主要由於凝固偏析問題，造成其均勻析出的控制在量產之產品產線均相當難達成。因此本研究藉由大鋼胚連鑄製程二冷配置和輕壓下參數適化，最後透過冶煉、連鑄、軋鋼串製程控制，有效提高其生產穩定度，使鋼胚抗粗晶合格率完全符合要求。

關鍵字

偏析 ； 加鈮鋼 ； 連鑄 ； 凝固

並列摘要

Gears and transmission shafts are usually used to provide the toughness of the body by adopting the low-carbon alloy steels such as SCM420, SCr420, and then carburizing treatment is used to improve the wear resistance and fatigue life of the surface. SCr420 was expanded in production, the grain size evaluation was often inconsistent, and the qualified rate of steel products was only 11%. After analysis, it was determined that the grain size was inconsistent, mainly due to the problem of solidification segregation, which caused its non-uniform precipitation in mass production. This study uses the secondary cooling and soft reduction parameters to adjust, and finally through the refining, continuous casting, and rolling steel string process control, the production stability is effectively improved, and the steel of anti-coarse grain pass rate is completely meet the requirements.

並列關鍵字

Segregation ； Nb-added steel ； Continuous Casting ； Solidification

參考文獻

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