中文摘要：

中锰钢连铸坯容易出现角横裂。用Gleeble热模拟试验机研究了中锰钢热塑性,并通过微观组织表征和热力学分析研究了第Ⅲ脆性区原因。结果表明,中锰钢在550~775℃出现第Ⅲ脆性区,形变诱导铁素体相变导致变形温度750℃的样品塑性最低。实际生产中应控制二冷区水量,提高连铸坯角部温度避免角部裂纹。

英文摘要：

Transverse corner crack is likely to occur on slab of medium manganese steel. The thermoplastic of medium manganese steel was studied using Gleeble thermal-mechanical simulator,and the causes of the brittle region Ⅲ were analyzed through microstructure characterization and thermodynamics analysis. The results show that the brittle regionⅢwas occurred at the temperature of 550-775 ℃,and the ferrite phase transformation induced by deformation cause the lowest thermoplasticity at the deformation temperature of 750 ℃.Therefore,at the practical process,the quantity of water in the secondary cooling zone of continuous casting should be controlled carefully to avoid the corner crack of continuous cast billet.