The application of crack prevention techniques is badly needed in various industries. There are many practical applications, such as in space flight and aviation, shipping, military affairs and machine manufacturing. The current density distribution, temperature field distribution of flow around the crack tip and the heat affected of two cracks are derived theoretically in view of the pulse discharge in metal component with double semicircle immerged crack. A three-dimensional finite element model with semicircular embedding crack is established by finite element software ANSYS to analyze the temperature filed. The distribution law of temperature field is consistent with the results of theoretical calculations and numerical results, and the maximum temperature error and relative error are 75.560 ℃ and 3.150% respectively. By pulse discharge experiments, the crack tip melts and passivated after pulse discharge.