Crystal orientations of creep damaged Type 316 stainless steel (SUS316L) were measured by 3 organizations using the same specimens, passed in a round robin, in order to investigate the scatter in material damage assessment using the electron backscatter diffraction (EBSD) technique. Two misorientation parameters, KAM (Kernel average misorientation) and GOS (Grain orientation spread), were calculated using mapping data of measured crystal orientations. It was shown that KAM and GOS correlated well with the degree of creep strain. However the scatter in GOS was smaller than in KAM. The GOS parameter showed an excellent correlation with both of the creep strain and creep damage ratio. It was concluded that the GOS parameter can be used for evaluation of the creep damage. The empirical relationship between GOS parameter and the degree of the creep damage can be shared regardless of the SEM/EBSD system used.
