采用化学侵蚀、彩色金相和电子探针（EPMA）等方法对304L奥氏体不锈钢连铸板坯宏观组织及其板坯表层残留铁素体的形貌、化学成分、质量分数和夹杂物进行了分析，并采用JMatPro 软件对304L不锈钢1 000～1 600 ℃的凝固过程进行了热力学计算。结果表明：304L的凝固模式为FA模式；304L不锈钢板坯表层树枝晶发达，富Cr贫Ni的残留铁素体呈点状、棒状、骨骼状分布；高温铁素体质量分数平均值为8.57%；板坯表层夹杂物都呈现为球状，类型为CaO-SiO2-Al2O3-MgO。

The morphology， composition， content of residual ferrite and inclusions in 304L slab surface layer was studied by chemical etching， metallographic test， SEM and EPMA method. The phase transformation of 304L at 1 000-1 600 ℃ was analyzed by JMatPro software. The results show that the solidification mode of 304L stainless steels is Mode FA； the morphology of residual ferrite enriched in Cr and depleted in Ni is skeletal， dot and stick； the average content of residual ferrite is 8.57%； the spherical CaO-SiO2-Al2O3-MgO inclusions are the main inclusion in the surface layer of 304L austenitic stainless steel slab.