大断面圆坯凝固组织及力学性能分析  

Mechanical properties and solidification structures of large round bloom

作　　者：孙涛[1] 岳峰[1] 林寒[1] 马忠存 李瑛 郭鑫 

机构地区：[1]北京科技大学冶金工程研究院,北京100083 [2]北满特殊钢有限公司,黑龙江齐齐哈尔161041

出　　处：《炼钢》2016年第1期66-69,共4页Steelmaking

摘　　要：研究了在不同结晶器电搅电流条件下大断面圆坯柱状晶区和等轴晶区的常温力学性能差别,通过金属原位统计分布分析技术和常温拉伸试验研究了柱状晶区和中心等轴晶区的疏松程度、抗拉强度和伸长率的差别,并定性分析了造成这种差别的原因。试验结果表明,随着结晶器电磁搅拌电流的增加,柱状晶区和等轴晶区的疏松程度均有所减轻,抗拉强度均有所增加,伸长率大致呈降低趋势。同一结晶器电磁搅拌电流强度条件下,柱状晶区的疏松程度好于等轴晶区;等轴晶区各个方向的抗拉强度相差不大,柱状晶区沿径向的抗拉强度大于垂直径向方向,并且等轴晶区抗拉强度均明显高于柱状晶区;等轴晶区2个方向的伸长率差异与柱状晶区相比相对较小。The difference of room temperature mechanical properties between the columnar crystal and the center equiaxial crystal of large round bloom solidification structures obtained by the different current intensity of mold electromagnetic stirring （MEMS） was investigated. Moreover, the difference of porosity degree, tensile strength and tensile elongation between the columnar crystal and the center equiaxial crystal was studied by original position analysis （OPA） method and tensile tests at room temperature. And then the reason for the results was analyzed qualitatively. The results show that the porosity degrees of columnar crystal and center equiaxial crystal are both reduced, the tensile strengths are increased, and the tensile elongations are roughly decreased with the increase of the current of MEMS. The porosity degree of columnar crystal is better than center equiaxial crystal under the same current of MEMS. The tensile strengths along different directions of center equiaxial crystal are almost same, but in columnar crystal the tensile strengths along the radial direction of columnar crystal are higher than the vertical to radial direction. Besides, the tensile strengths of center equiaxial crystal are obviously higher than those of columnar crystal. The difference between tensile elongations along different directions of center equiaxial crystal is smaller than that of columnar crystal.

关 键 词：大断面圆坯 结晶器电磁搅拌 疏松程度 抗拉强度 伸长率 

分 类 号：TF777.4[冶金工程—钢铁冶金]