One major success of the gStent-BE as a standard test stent is the consistent fracture location during axial fatigue loading. All reported fractures occurred at the bridges and for a given grip configuration, the 50% survival level was remarkably consistent from lab to lab, and the results are consistent with FEA predictions.
We found the median fracture level to be +/-1.23% motion (testing was performed with a 16mm gage length). When this loading condition is imposed on a Finite Element Model of the gStent-BE, it produces a peak alternating stress of 340 MPa. The contour plot from FEA shown below correctly identifies the peak location where fractures of the gStent-BE occur during axial fatigue. The mean stress in this case was near zero, as the loading was essentially fully reversed.
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