Method for acquiring acoustic emission frequency band of material crack damage

A material crack damage acoustic emission frequency band acquisition method comprises the following steps: establishing an I-type crack opening displacement expression through one-dimensional statics and boundary conditions, and obtaining a crack propagation displacement expression according to the opening displacement expression. And establishing a deformation moment tensor theoretical expression to conform to a loading form of finite element simulation, and substituting the opening displacement expression and the expansion displacement expression into the deformation moment tensor theoretical expression to obtain an acoustic emission source equivalent mechanical model of the I-type crack. On the basis of an equivalent mechanical model, various cracking processes at different loading rates and different expansion speeds are simulated by using COMSOL, and corresponding crack damage acoustic emission signals are obtained. And finally, processing and summarizing the acoustic emission signals to obtain a frequen