管线钢连铸板坯横截面元素的原位统计分布分析

Original position statistic distribution analysis of the elements in cross section of pipe line steel continuous casting slab

管线钢作为石油、天然气等管道运输的主要材料,其元素分布及组织结构对管线钢强度和韧性有较大影响。实验采用原位统计分布分析技术对管线钢连铸板坯板宽中心到板宽1/4处的中心区域中C、Mn、P、S、V、Ti、Nb元素的偏析和分布状态进行了定量统计分析研究。采用最大偏析度、统计偏析度、统计均匀度等指标对各元素的偏析分布进行了定量表征。研究结果表明,C、Mn、P、S、V、Nb元素的偏析分布形式基本类似,都在板厚中心线附近和板宽1/4处的厚度方向存在由局部富集区域组成的带状偏析带。其中,C、P、S元素的偏析较为严重,统计偏析度达到20%以上。Ti元素没有观察到明显的偏析,在整个分析区域分布比较均匀。

The pipe line steel is the main material of pipeline transportation for petroleum and natural gas.The elemental distribution and structure has great influence on the strength and toughness of pipe line steel.The segregation and distribution of C,Mn,P,S,V,Ti and Nb in central area from center to 1/4slab width of continuous casting slab of pipe line steel were quantitatively analyzed and investigated by original position statistic distribution analysis technology.The segregation distribution of elements was quantitatively characterized using the indexes including maximum segregation degree,statistical segregation degree and statistical homogeneity degree.The results indicated that the segregation distribution form of C,Mn,P,S,V and Nb was almost similar.A ribbon segregation area composed of partial rich regions existed near centre line and 1/4width in slab thickness direction for all elements.The segregation of C,P and S was relatively severe,and the statistical segregation degree was above 20%.The obvious segregation of Ti was not observed,and its distribution in whole analysis area was uniform.