高钢级管线钢的组织特征和强韧性

Structure Feature and Strength-Toughness of High Grade Pipeline Steels

背散射(EBSD)和扫描(SEM)电子显微镜及力学性能试验表明,微合金化X70、X80和X100管线钢的组织由针状铁素体、粒状贝氏体和少量下贝氏体组成;随钢的有效晶粒尺寸降低、贝氏体含量增加以及组织均匀性提高,高钢级管线钢的强韧性明显增加。

The test results with electron backscattered diffraction （EBSD） and scanning electron microscope （SEM） study and mechanical properties examination show that the structure of microalloying X70, X80 and X100 pipeline steels consists of acicular ferrite, granular bainite and a little lower bainite, and with decreasing effective grain size, increasing bainite content and improve structural homogeneity the strength and toughness of high grade pipeline steels increase obviously.