Observation of microstructure of X80 pipeline steel (/% : 0.043C
0.25Si
1.86Mn
0.085Nb
0.00lTi
0.028Al
0.0027N) has been carried out by using environmental scanning electron microscope
and characteristics of structure and grain-texture orientation of the pipeline steel are analyzed by X-ray diffraction ( XRD) and electron backscatter diffraction ( EBSD) technique. Results show that with increasing
{112}〈11
0〉、{110}〈110〉
orientation and small-angle boundary ratio
the pipeline steel's drop weight tear test ( DWTT) shearing area ratio enlarges and the toughness of steel increases; with decreasing finishing rolling temperature and increasing cooling rate after rolling
it is a- vailable to get more acicular ferrite and favlurable to DWTT performance.