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The crack propagation behavior can be tuned from unstable to stable manner without sacrificing the crack initiation during the opening mode test.
The elastic waves interfering with the plastic process zone on the crack front is proposed to explain such dynamic crack instability.
In turn, crack propagation patterns, as strength, are greatly affected by the mechanical and geometrical characteristics of the initial flaw.
Therefore, a unified local approach is feasible to model both crack initiation and crack propagation.
The results indicated a strong influence of stress waves on crack-propagation behavior and crack branching.
It is also shown that the two-dimensional Cotterell-Rice theory for the effect of tensile stress acting parallel to the crack surface on the stability of crack path is valid for the axisymmetric crack.
The developed procedures simplify the analysis of the description of mechanical fields at a greater distance from the crack tip considerably.
It is shown that the local variation of curvature along the crack front and interaction between crack front perturbations at adjacent crack points must be considered to properly calculate the derivatives of the energy release rates.
It is revealed that the proposed simulation method can reproduce reasonably the crack initiation and propagation, and predict well the change of the mechanical behaviour due to the openings.

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