The ability of Ni-based superalloys to withstand temperatures in excess of 11000C makes them useful for applications in the hottest components in jet engines, gas turbines, and thrust engines. Increasing the efficiency of these gas turbine engines helps to reduce the fossil fuel consumption and the production of greenhouse gasses. A common mode of failure in these Ni-based superalloys is low cycle fatigue, in which narrow regions of high dislocation density, which are known as persistent slip bands (PSBs), can develop and lead to crack initiation. A detailed understanding of the formation and structure of PSBs has eluded researchers. In order to better understand PSBs, we have subjected a single crystal Ni-based superalloy PWA1484 to low cycle fatigue using a strain amplitude of 0.6%. The specimen was interrupted every few 1000 cycles to polish the surface in order to remove surface steps and prevent early failure. This ensured that the single crystal specimen would develop numerous PSBs for us to characterize. We utilized scanning electron microscopy (SEM) based electron channeling contrast imaging (ECCI) to examine the formation of PSBs and to study the dislocation behavior. Using ECCI, we were able to rapidly identify the presence of PSBs under optimal imaging conditions. The structure, morphology, and orientation of the PSBs will be presented, and the application of ECCI in rapidly identifying PSBs will be discussed
