Nucleation of micro crack for brittle fracture in magnetic field

The influence of magnetic field on the nucleation of micro crack for brittle fracture is studied. The dynamic equation of micro crack in magnetic field is deducted. Using the crack model of a single pile-up group of dislocation, the growth speed of micro crack at a low growth speed stage is derived. To understand the effect of the magnetic field on the nucleation, the mean nucleation rate of micro crack in magnetic field is obtained. The derived result on the mean nucleation rate of micro crack shows that the applied magnetic field could change the mean nucleation rate of micro crack. The way in which the mean nucleation rate varies with the field depends not only on the field but also on the magneto properties of material.