Numerical Analysis of the Relationship Between Kernel Average Misorientation and Cyclic Plasticity in Circular-Like Single-Edge Notches

This study constructs a kernel average misorientation (KAM) evolution model based on the crystal plasticity finite element (CPFE) model, simulating the cyclic deformation of circular-like single-edge notched (CL-SEN) specimens under variable strain amplitudes and mean strains. The relationship between KAM and cyclic plasticity (plastic strain amplitude and mean plastic strain) is analyzed. The results show that the CL-SEN does not affect the linear relationship between KAM and plastic strain amplitude. For the first time, a linear relationship between KAM and mean plastic strain is proposed, with the influence of strain amplitude on KAM being significantly greater than that of mean strain. Additionally, the distribution patterns of KAM and plastic strain are consistent, further confirming their close correlation. The findings enhance understanding of fatigue damage mechanisms and provide guidance for improving the fatigue performance of materials.