石油储罐用钢拉伸断口分层研究

Study on Tensile Layered Fracture of Petroleum Storage Plate

针对石油储罐用钢12MnNiVR拉仲断口分层的现象，利用扫描电镜、金相显微镜和电子探针进行了深入的分析和研究，结果表明，分层与不分层试样的断口处的组织情况有明显差异，分层试样中心的马氏体组织含量较多，偏析带上多有MnS和Ti（C，N）夹杂。通过分析与计算，分层试样的偏析指数均大于不分层试样的偏析指数，是导致拉伸断口分层的根本原因。

Tensile layered fracture phenomenon of petroleum storage plate 12MnNiVR is analyzed and studied by means of scanning electron microscope （ SEM）, optical microscope （OM） and electron probe. The results show that there is significant difference between the microstructure of the layered and not-layered sample, more martensite content in the center of layered sample, also some MnS and Ti （ C, N） inclusion in segregation band. By analysis and calculation, seg- regation value of layered sample is larger than non-layered sample, which is the main reason of the tensile layered frac- ture.