高锰高铝钢凝固组织的实验研究

Experimental Study on Solidification Microstructures of High Manganese and High Aluminium Steel

为研究高锰高铝钢的凝固组织,在实验室条件下采用真空感应炉冶炼了三种不同成分的高锰高铝钢。研究结果表明,高锰高铝钢的柱状晶组织比较发达,其晶体尺寸比较粗大;增加钢中的Al含量可以降低柱状晶区比例和晶体尺寸,随着钢中Al含量的增加,钢的热塑性也明显增强;在奥氏体晶界析出的铁素体会降低钢的热塑性,是诱发连铸坯角部裂纹的主要原因。

In order to study the solidification microstructures of the high manganese and aluminium steel,three kinds of high manganese and aluminium steels with different compositions were smelted in a vaccum induction furnace at laboratory.The study results showed that the columnar crystals of the steel were much more flourishing and so the sizes of crystals were thicker as well.Increasing the content of aluminium could reduce the ratio of columnar zone and the sizes of crystals.Meanwhile the thermal plasticity of the steel was enhanced with the increasing of the content of aluminium.Furthermore,the ferrite precipitation at the boundary of austenite would decrease the thermal plasticity of the steel,which was the main cause leading to form the corner cracks of a strand.