A method for predicting the high cycle fatigue weak-link point location of composite fan blade was proposed. Using the layup information file

a full-scale fan blade finite element model was established by normal extruding shell elements in ACP (ANSYS composite pre-post). Based on ANSYS-Workbench and Tecplot application program interface

the developed post-processing program completed the layup blade finite element data extracts and database creation. According to the composite material CLD (constant life diagram) model

the weak-link point index was applied to predict the location of blade high cycle fatigue failure. Case results showed that the blade failure location height did not exceed 40% of the entire blade height. First failure stress of 1st bending mode，1st torsion mode and 2nd torsion mode was layer normal stress

while 2nd bending mode

3rd bending mode and stripe mode failures first occurred in layer shear stress. The layer normal stress weak-link point of blade bending mode was located in chord middle; the torsional mode vibration stress amplitude points were all structural plys

and S3 weak-link point was near the trailing edge. Compressive average stress could cause high cycle fatigue blade failure

and the area with a smaller static stress value could become a weak-link point.