双辊连铸法制取3.0%Si硅钢薄带的组织与性能

Microstructure and Properties of 3.0% Si Steel Prepared by Twin-Roll Casting Process

薄带连铸技术是目前冶金及材料领域的前沿高技术 ,硅钢被认为是该技术中最有开发潜力的钢种之一。文中采用双辊法连铸工艺研制 3.0 %Si无取向硅钢薄带 ,研究了铸带坯组织特征及其冷轧退火后的组织转变。铸带随铸轧工艺和冷却工艺不同 ,表现为全等轴晶组织或中心为等轴晶 ,表层为柱状晶组织 ,铸后快速冷却有利于获得组织细小的铸带 ,提高冷加工性能。铸带坯经冷轧及高温退火后 ,基体上出现不同于传统工艺的Fe3Si有序化相。经测试 ,双辊法研制的无取向硅钢磁性能达到传统生产方式的水平。

Thin strip casting is one of the most potential technologies in thin strip product. Silicon steel is also considered as one of the most promising alloys produced by twin roll process. Fe-3%Si strips were produced by twin-roll casting process. Casting microstructure and annealing microstructure of silicon-steels were analyzed by microscope, TEM, EDA and XRD. There are two kinds of solidification structures: columnar crystal and equiaxed crystal zones. By controlling the process parameters properly, the columnar grains could transform into equiaxed grains, the grain of the as-cast strips was further refined by increasing in the cooling rate during solidification and the secondary cooling. The microstructure of casting strips are α-Fe with disordering Fe 3Si phase. The disordering Fe 3Si will transform into ordering Fe 3Si after cold rolling and heat treatment. Electric and magnetic properties of 3.0%Si silicon steels prepared by Twin-roll process can correspond with that produced by conventional method.