1018高錳碳鋼之連鑄控制技術建立

The Study of 1018 High Manganese Carbon Steel in Bloom Continuous Casting Process

10.30069/MM.202303_67(1).02

蔡德昌(D.C. Tsai)；郭春億(C.Y. Kuo)；傅俊融(C.J. Fu)；呂佳峰(C. F. Lu)

偏析 ； 高錳鋼 ； 連鑄 ； 凝固 ； Segregation ； High Manganese Carbon Steel ； Continuous Casting ； Solidification

鑛冶：中國鑛冶工程學會會刊

67卷1期（2023 / 03 / 01）

18 - 24

繁體中文;英文

在C-Mn合金鋼中，由於Mn元素會降低Ar3相轉變溫度，所以Mn主要為沃斯田鐵穩定元素。在後續冷卻過程中，溶質偏析造成沃斯田鐵（低Mn區）先變態形成肥粒鐵相，碳進一步擴散至鄰近的沃斯田鐵（高Mn區），最終相變態成波來鐵。當鋼胚存在中心偏析時，鑄胚軋後冷卻將出現變韌鐵或帶狀麻田散鐵組織，在熱應力和相變應力作用下可能導致鋼胚內部裂紋產生。另外在偏析帶周圍容易沉積大量夾雜物，如硫化物、矽酸鹽等，加速了中間裂紋的形成和擴展。因此本研究主要藉由大鋼胚連鑄二冷配置和輕壓下製程適化，進一步改善中心偏析和縮孔缺陷，使鋼胚品質符合客戶要求。

In C-Mn alloy steel, the Mn element will reduce the Ar3 phase transition temperature as stabilizing element of austenite. In the subsequent cooling process, the solute segregation caused the austenite (low Mn region) to form a ferrite, and the carbon further diffused to the adjacent austenite (high Mn region), transformed into pearlite finally. When the center segregation in the strand, bainite or martensite will appear after the cooling process of billet rolling. The thermal stress and phase transformation may cause internal cracks in the billet. In addition, a large number of inclusions, such as sulfides and silicates, are easily deposited around the segregation zone, which accelerates the formation and propagation of intermediate cracks. Therefore, in this study, the secondary cooling pattern and the soft reduction process are mainly used to further improve the center segregation and shrinkage defects, so that the quality of the product meets the customer's requirements.

1. Majka, T.F.,Matlock, K.(2002).Development of Microstructural Banding in Low-Alloy Steel with Simulated Mn Segregation.Metallurgical and Materials Transactions,33A,1627-1637.
2. Xue, Chunfang,Hu, Yisu(2004).Effect of Nb Precipitation on the Grain Fining in Nb-microalloyed Steel.MetallurgcalCollections,152,41-43.
3. Zong, Yun,Zhao, Li Ping(2011).Continuous Cooling Transformation Behaviour and Microstructure of Low Carbon Nb-bearingMicroalloyed Steel.Materials for Mechanical Engineering,35,31-38.
4. 李士同(1999)。Fe-Mn-C 合金中的 C-Mn 偏聚及其對相變的影響。自然科學進展，558-563。
5. 姜雪(2015)。哈爾濱工業大學。