In this paper, we focus on the numerical modeling of the reliability of the self-piercing rivet process. Tensile tests were conducted on SPR joining Al (ECO Al7021-T7) specimens. In addition, a 2D axisymmetric FE model was generated to characterise the SPR joining process on the extruded Al sheets. The simulations were carried out using the LS-DYNA, one of the representative explicit finite element codes. A tensile simulation of the riveted two Al plates was performed to investigate the tensile behaviour of self-piercing rivet parts. An FE analysis results showed comparatively good agreement with experiments.

In this paper, we compared the performance of the mechanical inertia and electronic inertia used in the friction coefficient measurement process, as this is the main function of the braking performance tester. The comparative test was carried out 36 times under mechanical inertia and electronic inertia. Stop braking was performed at various braking speeds (120, 160, 200, 220 ㎞/h), and at various contact force conditions (8, 18, 25 kN). We compared the instantaneous coefficient of the friction, the average coefficient of the friction, the braking force, and the braking distance with the mechanical inertia and the electronic inertia, by taking the average of the three tests we performed each for braking velocity and contact force. In addition, the friction coefficient ratio and the energy ratio were calculated. As a result, it was confirmed that the test using the electronic inertia compared to the test using the mechanical inertia appropriately reflects the bearing frictional force and the rotational resistance loss of the tester, and the kinetic energy is consumed as the braking energy without loss.