Quantification of splitting in X80 pipeline steel

The results of in-depth analysis of microstructure and crystallographic texture of several industrial batches of line pipes with known full-scale burst test results are presented. Several microstructural features promoting splitting are highlighted and quantified using electron back-scattered diffraction (EBSD) data. The actual splitting intensity is evaluated by means of Charpy tests in the direction of pipe wall thickness (Z-direction) and correlates with the microstructural parameters determined by EBSD analysis. This knowledge can be used in the design of thermo-mechanical controlled processing (TMCP) dedicated to production of splitting-free steel