显微组织与晶体学织构对X80管线钢拉伸强度各向异性的影响

Effects of microstructure and crystallographic texture on anisotropy of tensile strength of X80 pipeline steel

利用室温拉伸试验检验了X80管线钢中厚板与轧向成0°（纵向）和90°（横向）方向的屈服强度和抗拉强度,通过金相观察和电子背散射衍射（EBSD）技术对管线钢组织形貌、晶界分布和晶粒尺寸进行了分析,用X射线衍射测算了钢板的取向分布函数（ODF）,讨论了显微组织特点和晶体学织构对管线钢拉伸强度各向异性的影响。结果表明：具有不同横、纵向拉伸强度的试样,横截面和纵截面组织类型和形貌基本相同,且横截面均具有较小的晶粒尺寸;织构是造成管线钢拉伸强度各向异性的主要原因。

The yield strength and tensile strength of X80 pipeline steel plate at 0°, 90° to the roiling direction were tested by the tensile testat room temperature, then the morphology of microstructure, grain boundary distribution and grain size were analyzed by the metallographi（：observation and electron back scattering diffraction technique, and orientation distribution functions （ODF） of the plate was analyzed by theX-ray diffraction, and effects of microstructure characteristics and crystallographic texture on the anisotropy of tensile strength of the pipelinesteel were discussed. The results show that the type and morphology of microstructure of the specimen with different tensile strength attransverse and longitudinal directions are basically the same, and the grain size at transverse section is smaller, meanwhile the anisotropy oftensile strength should be attributed to crystallographic texture.