Metal-Composite structures have a wide array of applications, most notably in the automotive, marine, and aerospace disciplines. The joining mechanism between the material constituents is arguably the most critical component of any structure. While the mechanical behavior of structural joints under static and cyclic loading conditions has been thoroughly investigated, very little research has been performed at impact rates of loading. Since virtually every structure is subjected to time-dependent stimuli, it is essential to understand the behavior of structural joints in the dynamic regime. In this study, a Split Hopkinson Pressure Bar (SHPB) was developed to induce an axial tensile stress pulse on Aluminum/S2-glass single-lap joints. The effect of joining method on strength and failure mode was investigated for bolted, bonded, and hybrid (bolted/bonded) joints at varying edge distance (e) to bolt diameter (d) ratios, a critical parameter in single-lap joints. It was demonstrated that joint strength increases with e/d and that failure mode transitions from catastrophic failure to progressive bearing damage between e/d 3 and 4. The findings also suggest that hybrid joints with lower e/d ratios exhibit comparable strength to bolted joints at higher e/d ratios. Effects of alternative material combinations and surface preparation on joint performance were also considered in Aluminum/E-glass and Advanced High Strength Steel (AHSS)/S2-glass single-lap bolted and hybrid joints. Additionally, the mechanical behavior of single-lap joints at elevated temperatures was investigated at 80°C. Both bolted and hybrid joints over the investigated range of e/d ratios exhibited a 20-30% decrease in joint strength. Design guidelines were established for single-lap structural joints with consideration for e/d ratio, joining method, material constituents, surface preparation, and environmental effects.
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