Papers by Keyword: Self-Piercing Riveting

Abstract: The increasing use of multi-material constructions lead to a continuous increase in the use of mechanical joining techniques due to the wide range of joining possibilities as well as the high load-bearing capacities of the joints. Nevertheless, the currently rigid tool systems are not able to react to changing boundary conditions, like changing the material-geometry-combination. Therefore research work is crucial with regard to versatile joining systems. In this paper, a new approach for a versatile self-piercing riveting process considering the joining system as well as the auxiliary joining part is presented.

Abstract: Due to increasing demands regarding ecological and economic specifications in vehicle design, the effort required for production is continuously increasing. One trend is the increased use of multi-material systems, which are characterised by the use of different materials such as high-strength steels or aluminium alloys. In addition to the varying mechanical properties of the components, an increased number of variants accompanied by different geometries is leading to increasing challenges on body construction. For the assembly and connection of the individual components, conventional joining methods reach their limitations. Therefore, new joining methods are necessary, which feature properties of versatility and can adapt to process and disturbance variables. One way of achieving tailored joints is to use a tumbling self-piercing riveting process. For the design of the process route, numerical investigations are necessary for which a characterisation of the friction properties is necessary. This paper therefore investigates the contact and friction conditions that occur in a tumbling self-piercing riveting process. The individual contacts between the process components are identified and based on this, suitable processes for the characterisation of the friction factors - and coefficients are selected and performed.

Abstract: Due to continuously increasing requirements on lightweight sheet metal constructions, new processes and technologies are necessary to face current and future challenges. A trend in lightweight construction is the multi-material mix with sheets of different geometric and mechanical properties. To manufacture these so-called composite structures, new joining technologies and methods are required. One possibility is the further development of the self-pierce riveting joining process. For the simulation and evaluation of new and adapted processes of self-pierce riveting, numerical models are used to investigate process parameters and constraints. Besides precise material models for the numerical simulation of this joining process, the identification of friction parameters between the individual sheets and rivet elements is necessary to achieve exact results. Thus, a method is necessary to identify the friction coefficients between rivet elements and sheets. Such a method is presented and evaluated in this work. Different process parameters like the relative speed are varied for the experimental investigations and an analysis of the respective influence on the resulting friction coefficients is conducted. For the use of the test set-up, coefficients of friction are determined for rivet elements “RIVSET^® C 5.3x5.5” (Böllhoff GmbH) coated with Almac^® in combination with two different sheet materials HCT590X+Z and EN‑AW 6014.

Abstract: Over the past years engineering has established itself in many areas of production technology on the basis of simulation methods. Efficient tools and software applications for the development and planning of products, machines and systems have been developed which allow virtual analyses especially for critical areas, e.g. micro structural analysis’s, forming processes or joining applications. However, these are often isolated solutions which only cover one particular aspect and are not complete calculation tools. This is often caused by data transfer between simulation programs. There are hardly any automatic links between software tools which often come from different providers. Often data formats have to be converted first and then transferred manually. Therefore, interdependencies can only be taken into consideration to a small extent and with a high expenditure of resources. This affects the quality of numerical results and hence the development and optimization process. Consequently, the necessity of a process chain simulation which covers all production steps similar to a virtual factory becomes obvious. This automatic simulation should make it possible to consider the numerical results from micro structure calculation to the manufacturing of the composite tools successively and thus contribute to having a nearly fault-free perfected process for the real factory.

Abstract: Adopting self-piercing riveting (SPR) joining, a new light sheet material joining method, to examine the joining of copper-titanium alloy (H62-TA1) sheet and titanium-aluminum alloy (TA1-Al5052) sheet. Also, using quasi-static mechanical test to figure out mechanical properties of H62-TA1 SPR single-lap joint and TA1-Al5052 SPR single-lap joint. In this study, using Dixon guidelines to eliminate abnormal value and adopting coefficient of variation method to validate reliability of test datum. The results show that failure mode of H62-TA1 joints is that the rivets are pulled out, failure mode of TA1-Al5052 joints is that the bottom sheet fracture. And tensile displacement and energy absorption of H62-TA1 joints are higher than that of TA1-Al5052 joints.

Abstract: By analyzing the modeling characteristic of ground and front-end impact areas, the modeling control strategy is proposed with regard to ventilation cover plate, engine hood, engine hood leading edge, fender and radiator grille, front bumper. The Riveting point support area concept is presented accordingly. Furthermore, the optimal position relationship of bumper modeling support area is obtained using the ADMAD under a given stiffness of bumper components. The result indicates that the optimized modeling can control the manipulation easily and helps to improve performance of driver assistance.

Abstract: This paper studied the performance of self-piercing riveting (SPR) and adhesive hybrid joints of different adhesive, including strength, capacity of energy absorption, failure mode and failure mechanism of the hybrid joints. The performances of SPR-adhesive hybrid joints were compared with SPR joints. SPR-adhesive hybrid joints and SPR joints were tested under a tension loading. The test results showed that adhesive have a function of improving the strength of SPR joints; however, the capacity of energy absorption of SPR joints was weakened. While the adhesive have no effect on the failure modes of SPR joints. When appropriate adhesive was selected, the overall performance of SPR-adhesive hybrid joints was superior to SPR joints. In a word, the combination of SPR and adhesive could get a well jointing structure.

Abstract: As a result of the trend towards lightweight construction in manufacturing, there has been a significant increase in the use of self-pierce riveting (SPR) joints in engineering structures and components. Mechanical structures assembled by SPR are expected to possess a high damping capacity. The aim of this paper is to provide an experimental technique for the investigation of the forced vibration behavior of SPR joints. The dynamic test software and the data acquisition hardware were used in the experimental measurement of the dynamic response of the SPR joints. The frequency response functions of the SPR joints of different rivet number were measured and compared.

Abstract: This paper studied the performance of self-piercing riveting (SPR) of aluminum and copper alloy sheet. The SPR process of two copper alloy sheets was analyzed by experimental tests and finite elements stimulation, and good agreements between the simulations and test results of SPR process were obtained. Two different specimen geometries were adopted in experiment: a lap-shear type specimen and a T type specimen. The influence of combination of different materials on the static strength of SPR joints were studied through the tensile-shear and peeling experiments, and the strength of the SPR joints were evaluated by the force-displacement curves of two type specimens. The failure mechanisms corresponding to the static strength were also discussed. On the other hand, the engineering stress - strain curves of two materials have also been studied roughly. These results could provide designer engineers with some application messages of SPR.