Dynamic Analysis And Fatigue Analysis Of SPR Joints

The self-piercing riveting (SPR) is a new technology used in connecting sheet metal, the process is simple, only one step, SPR has the advantages that spot welding does not have .SPR is known as the next-generation connection technology of car lightweihting.This paper studies dynamics performances,fatigue properties and the simulation of single-lap SPR joints, including the modal analysis of single lap self-piercing riveted joints, the SPR process simulation and the crack growth in stretching process simulation,and the analysis of static tensile test. The simulation results match with the test,which gives foundation and provides a theoretical basis for future research,at the same time, it can reduces the test costs and save a lot of manpower and material resources, so it has a certain reference value.The article studies the dynamic performance of the single-lap SPR joints, the model analysis is mainly. There are two cases in model analysis,one is with crack,the other isn't. The paper studies each case under, different parameters,including density, elastic modulus, Poisson ratio and crack length.By using ANSYS/FE-SAFE to analysis the fatigue performance of single-lap self-piercing riveted joints, including fatigue life and minimum safety factor, then analog the S-N curve。In addition, the paper also studies impact of load amplitude,surface processing factor,load frequency on fatigue performance.By using ANSYS / FE-SAFE to do SPR process simulation, the simulation results match with test results. Through the riveting process simulation to study the riveting process, energy changes, the internal stress contours and the internal pressure contours and so on. The paper also studies the impact of the density, elastic modulus, yield strength, friction coefficient and material type on lap riveting processes.With ANSYS/FE-SAFE to simulate the crack growth in stretching process, the paper studies the force and deformation conditions of rivet and the upper plate and the under plate, it also gets internal stress contours, the force-time curve, the internal pressure contours, energy change and crack growth rate curve.Finally, through the static tensile test to study the self-pierce riveting joint tensile strength. In the tensile test, the rivets were pulled out from under the plate or the under plate is fracture.