The Use of Aluminium Alloy after High Plastic Deformation for Joining Riveted Structures

This paper presents the results of a static and dynamic tensile test of an Al7.5Mg aluminium alloy taken from round bars made in the technology of hydrostatic extrusion. It is planned to use the Al7.5Mg aluminium alloy for joining riveted structures. Based on the obtained results, the nominal and true characteristics of the Al7.5Mg aluminium alloy, depending on the strain rate in the range from 0 to 2000 s^-1, were developed. The failure criterion for tension was determined. The material characteristics were approximated by the Johnson-Cook equation, which can be used in CAE (computer-aided engineering) programs to simulate the impact processes. FEM (finite element method) simulation of the impact of the hammer on the part of the riveted aircraft structure was performed. The FEM simulation results were compared with the experimental results on a drop hammer to verify the material model. The following results were obtained: yield strength R = 395.3 MPa; strength limit R = 523.1 MPa at deformation 0.067; Young's modulus E = 7.9 × 10⁴ MPa. The AL7.5Mg alloy after hydro-extrusion has favourable plastic and strength properties.