Abstract:Crack growth is one of main failure modes of gear drive,and the effects of crack position on the crack growth is obviously.In order to study the effects of crack position on the tooth crack growth of a gear pair,several models of double crack gear pair with reference circle crack and root crack in neighbour teeth were proposed.The finite element models of gear pair with three teeth meshing were established by the ABAQUS software,and the value of principle stress and the value of stress intensity factor near the crack tip were calculated.The relationship between the reference crack growth life and the root crack growth life was discussed by Pairs equation.The results show that the stress at the crack tip of gear pair in single tooth meshing is greater than that in double tooth meshing,and the bending stress at the crack tip is obviously greater than the shear stress.Under the same load and crack depth,the stress intensity factor at the crack tip of the root is greater than that at the crack tip of the reference circle.Under the same load,the crack growth life of the gear with root crack is smaller than that of the gear with reference crack.In the process of crack growth,the ratio of crack depth between root crack and reference circle crack is nondetermined value,and the ratio is independent of load.