Finite element simulation and experimental verification of dynamic rigidity of magnesium alloy bolted joints

This study has developed a novel analyzing method to clarify mechanical and dynamic characteristics of bolted joints based on multi-material structures, including magnesium alloy. For this research, specimen of magnesium alloy bolted with other metal materials and finite element meth od (FEM) were used to see natural frequency, vibration modes, clamping force, and interfacial stiffness of t he jointed parts. A series of hammering tests and numerical simulations were performed to obtain the relationship between the natural frequency and the clamping force, and the effect of the magnesium alloy was investigated. The numerical simulations were executed by the FEM based on a mechanical model to simulate the mechanics of th e real contact area between bolted joints interfaces. The results reveal that the Young’s modulus of the magnesium alloy affects the interfacial stiffness of the jointed parts, and the natural frequency of the magnesium alloy bolted joints asymptotically increases to the constant value under lower clamping force than the other joints . The rigidity of the constituent materials has more influence on the deformation shape with many nodes and ant inodes. The interfacial element between the washer and clamped member material is not necessary since the i nfluence factor is very minimum compared to the influence between the clamped materials interfacial elements.