Creep damage assessment of HR3C austenitic steel by using misorientation parameters derived from EBSD technique

The evaluation ability of misorientation parameters and Kikuchi band parameters on creep damage of HR3C austenitic steel is reported in this paper. HR3C steel samples were subjected to the creep process for 475, 756, 1240, and 1300 h, respectively. During the creep process, the average kernel average misorientation (KAM) and grain reference orientation deviation (GROD) increased significantly overall as the creep time increased, while the average mean angle deviation (MAD) and band contrast (BC) did not show significant changes. When comparing GROD and KAM, it was found that the variation range of GROD is larger and the variation trend is monotonous, making GROD more suitable for evaluating the creep damage of HR3C steel. Subsequently, the physical mechanism of GROD is derived and studied.