Novel Form-Fit Blind Rivets and Lock Bolts

The advantages of novel form-fitting blind rivets and lock bolts are discussed. The development of these joining elements was assisted by simulations performed with ANSYS, a multi-purpose Finite Element Method (FEM) software program. 2D and 3D FEM models were used for feasibility and parameter studies, respectively.

Results of initial tests with Aluminium specimens under quasi-static showed an improvement in the yield strength by a factor of at least two. In the case of cyclic loading the fatigue life of the joints is improved at by a factor of at least 5.10³.

Subsequent tests carried out with FF blind rivets and lock bolts with different steels and Aluminium alloys show that the improvement in both static strength and fatigue life increase with the strength of the base material, the fatigue strength in some cases being higher than the load at joints made with state of the art rivets and lock bolts  slip.

It is expected, that these blind rivets will gradually replace most current blind rivet and lock bolts, because they offer a far superior performance without or at the outmost a marginally higher cost. In many cases, fitting bolts could also be replaced with considerable cost savings and improved mechanical performance.