Numerical and experimental investigations of self-piercing riveting

Abstract

Self-piercing riveting (SPR) is a new high-speed mechanical fastening technique which is suitable for point-joining dissimilar sheet materials, as well as coated and pre-painted sheet materials. With an increasing application of SPR in different industrial fields, the demand for a better understanding of the knowledge of static and dynamic characteristics of the SPR joints is required. In this paper, the SPR process has been numerically simulated using the commercial finite element software LS-Dyna. For validating the numerical simulation of the SPR process, experimental tests on specimens made of aluminium alloy have been carried out. The online window monitoring technique was introduced in the tests for evaluating the quality of SPR joints. Good agreements between the simulations and the tests have been found, both with respect to the force-travel (time) curves as well as the deformed shape on the cross-section of the SPR joint. Monotonic tensile tests were carried out to measure the ultimate tensile strengths of the bonded joints, SPR joints and SPR-bonded hybrid joints. Deformation and failure of the joints under monotonic tensile loading were studied. The normal hypothesis tests were performed to examine the rationality of the test data. This work was also aimed at evaluating experimentally and comparing the strength and energy absorption of the bonded joints, SPR joints and SPR-bonded hybrid joints.