Abstract:To study the semi-infinite plane problem including an embedded deflection crack and a micro-crack at any position under tensile load. Based on the continuous distribution dislocation method, the corresponding dislocation density integral equation was established, and its mechanical parameters were obtained by using the GAUESS-CHEBSHEV numerical integration method. The theoretical results are verified by finite element method. The buried depth and the distance from the microcrack center to the main crack tip will affect the stress intensity factor of the main crack tip; Compared with the case without microcracks, microcracks in some directions promote the growth of the main crack tip, while microcracks in other directions inhibit the growth of the main crack tip; The propagation direction of the main crack tip and the equivalent stress intensity factor are more affected by the horizontal microcrack than the inclined microcrack. The stress intensity factor at the tip of the main crack decreases with the increase of the crack embedding depth and the distance from the center of the microcrack to the tip of the deflected main crack; In time, microcracks will promote the growth of main cracks, while in time, they will inhibit the growth of main cracks; When the microcrack is in and, the propagation direction of the main crack will deflect clockwise from the original propagation direction, while when the microcrack is in and, the propagation direction of the main crack will deflect counterclockwise from the original propagation direction; Horizontal microcracks have more influence on the propagation direction of the main crack and the equivalent stress intensity factor than inclined microcracks.