高锰钢凝固特性及连铸工艺研究现状

State of art on solidification characteristics and continuous casting process of high manganese steel

高锰钢具有良好的强度、延展性及耐磨性等特性,正广泛应用于能源、交通、工程机械等领域。采用连铸替代传统模铸生产高锰钢可显著提高生产效率,正受到冶金企业的重点关注。但目前高锰钢连铸生产仍存在浇铸不畅、铸坯质量缺陷频发的问题,严重制约着高锰钢高效、高质化连铸生产。结合国内外研究学者前期研究工作,重点对高锰钢凝固特性基础研究和连铸实践两方面进行了回顾。首先,介绍了成分对Fe-Mn、Fe-Al二元相图,Fe-Mn-C、Fe-Al-C三元相图,Fe-Mn-Al-C四元相图的影响;高锰钢的成分对固液相线温度、密度、导热系数等热物性参数的影响,以及对凝固组织和析出物的影响。然后,结合高锰钢连铸生产实践,介绍了高锰钢连铸保护渣、冷却工艺和压下工艺设计和优化。虽然部分高锰钢已经实现了连铸替代模铸生产,但连铸坯质量问题仍然未得到根本性的解决,特别是高锰高铝钢连铸生产仍面临着相当大的困难。未来应持续开展高锰钢凝固特性方面的深入研究,并针对高锰钢凝固特性开展专用连铸工艺设计和开发,实现高锰钢连铸精细化控制,确保高锰钢连铸高效和高质化生产。

High manganese steel has good strength,ductility and wear resistance,and is widely used in energy,transportation,engineering machinery and other fields.Using continuous casting instead of traditional mold casting to produce high manganese steel can significantly improve production efficiency,and thus has been attracted the attention of metallurgical enterprises.However,there are still some problems in the continuous casting production of high manganese steel,such as poor castability and frequent strand defects,and these problems seriously restrict the continuous casting production of high manganese steel with high efficiency and high quality.Based on the previous research works of domestic and foreign researchers,the basic research on solidification characteristics and the practice of continuous casting of high manganese steel are reviewed.Firstly,the effects of composition on Fe-Mn,Fe-Al binary phase diagram,Fe-Mn-C,Fe-Al-C ternary phase diagram and Fe-Mn-Al-C quaternary phase diagram are introduced.The effects of high manganese steel composition on the thermophysical parameters,such as solidus and liquidus temperature,density and thermal conductivity as well as solidification structure and precipitations are all analyzed.Then,combined with the production practice of high manganese steel continuous casting,the design and optimization of mold flux,cooling process and reduction process of high manganese steel continuous casting are introduced.Although some high manganese steels have been successfully produced by continuous casting instead of mold casting,the quality defects of continuous casting strand have not been fully solved,especially the continuous casting production of high manganese and high aluminum steels still faces considerable difficulties.In the future,in-depth research on solidification characteristics of high manganese should be continued,and dedicated continuous casting process design and development should be carried out based on the solidification characteristics of high manganese steel to achieve precise control of high manganese steel continuous casting and ensure efficient and high-quality production of high manganese steel continuous casting.