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In this paper, a bolted joint of two prismatic parts subjected to a shear impact force applied in the structure’s longitudinal direction is studied. The base part is made from steel and the connected one is from aluminum alloy. An elastomeric layer is inserted between the assembled parts in order to reduce vibration resulting from external excitation. An equivalent dynamic model is developed to analyze the behavior of bolted structure. The formulation of the problem gives a system of nonlinear equations. Solving differential equations is based on Euler’s method. Dynamic responses which correspond to the two degrees of freedom of the model are shown. The joint nonlinear behavior strongly depends on the interface properties. A cubic stiffness and damping factor are considered for the layer in the model, which gives it more realistic responses. Experimental tests are done for a case study of bolted joint under transient hummer impact. Model results are agreed with those issued from experiments. The damping layer (DL) effect is experimentally observed as well as in the model results.

Indium–zinc in situ composites were fabricated and their viscoelastic properties studied over 8.5 decades of frequency. Material with 5% indium by weight was found to have a stiffness damping product (the figure of merit for damping layers) of 1.9 GPa at 10 Hz; 3 times better than the peak of polymer damping layers and over a wider frequency range. Material with 15% indium had a stiffness damping product of 1.8 GPa. The indium segregated in a platelet morphology, particularly favorable for attaining high damping from a small concentration, as predicted by viscoelastic composite theory.