Research on the relationship between early surface deformation and microstructure evolution of Ni-based single crystal alloy

Abstract

During the early service phase of Ni-based single crystal alloy (NSCA), the degree of its surface deformation is closely related to the service life. It is important to quantitatively characterize the surface deformation of NSCA from the microscopic scale. However, the studies on the quantitative relationship between the degree of surface deformation and the microstructure evolution of NSCA have not been found yet. Thus, we establish the theoretical relationship between the microstructure evolution of NSCA and its early surface deformation through nonlinear expression methods. The MD method is used to calculate the dislocation density change of NSCA in different crystal orientations, by which the variation of the characteristic parameter and the damage degree of NSCA are predicted. Moreover, the results of the MD simulation are consistent with the variation of nonlinear characteristic parameter obtained in the experiment, which further confirms the correctness of the theoretical relationship. This research will offer a theoretical basis for the predictive maintenance of aero-engine turbine blades.