Riv-Bonding of Aluminum Alloys with High-Strength Steels against the Favorable Joining Direction

In order to exploit the advantages offered by multi-material design, this work studies the feasibility of joining aluminum alloys with high-strength steels (HSS) against the favorable joining direction by using self-piercing riveting (SPR) combined with adhesive bonding, so-called riv-bonding. Therefore, riv-bonding of four joint configurations including different aluminum alloy sheets (AW-6014-PX, AW-6451-T4), HSS sheets (HC420LA, HC450X) and rivet types (C5.3×8.0-H4, U5.5×5.0-H6) was experimentally investigated. Moreover, riv-bonding of two joint configurations was exemplarily modeled using the Simufact Forming finite element (FE) software. The viscoelastic properties of the liquid adhesive layer between the sheets were substituted with “equivalent” elastoplastic properties to model the adhesive as solid with strain rate-dependent flow behavior. Good agreement of joint cross sections and force-displacement curves between experiments and simulations confirms that the presented numerical model of riv-bonding is suitable for predicting both the joinability of aluminum alloys with HSS and the final quality of hybrid joints.