Macroscopic modelling of Flow-Drill Screw connections

Abstract

This study focuses on the modelling of Flow-Drill Screw (FDS) connections in large-scale shell analyses. Macroscopic connection models for large-scale crash simulations were assessed for modelling of FDS connections between two aluminium plates. Of the investigated models were two commercial element-based and three commercial constraint-based models, as well as two new user-defined element-based models. All models were calibrated using cross tests in tension, shear and a mixed shear/tension mode. In order to assess the flexibility of the models two sets of experimental data were used. In the first one, a small screw was used to join two sheets of the same rolled alloy while the second set used a longer screw with a larger head to join a rolled alloy to an extrusion. The calibrated models were validated using a two-step approach involving benchmark and component tests. Of the commercial models, the constraint-based performed better than the element-based. The new user-defined models gave similar results as the commercial constraint-based models. From the obtained results, recommendations for modelling of FDS connections for large-scale analyses were formulated.