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Jaguar Cars, the luxury UK automaker, is developing a new car, the X350. For the first time, the company is to use aluminium body panels for the body shell. Aluminium can be difficult to weld so self‐piercing rivets are used for metal joining. The rivets are used in place of spot welding, but are applied by rivet setters attached to robots.

Describes how Jaguar Cars is evaluating a technology roadmap to assess future manufacturing processes.

Describes the major production line technologies that are under close scrutiny for the next ten years for use in the Jaguar Cars' production plants at Castle Bromwich and at Halewood, Merseyside, both in the UK. Technologies under review include ultrasonic welding, friction stir spot welding, laser welding and self‐piercing rivets.

The use of self‐piercing rivets is already used in production at Jaguar for the aluminium‐bodied XJ saloon. But developments of the process are already underway in readiness for the next new model. However, at the same time, engineers are examining other techniques including ultrasonic joining and friction stir spot welding, both of which at the subject of research work in the US and the UK. Use of pedestal guns and blow feeding devices is expected to bring improvements in cost.

Engineers at Jaguar are carrying out research and development, both in‐house and with various research bodies and universities to establish the most beneficial processes for the joining of aluminium sheet, extrusion and cast components that go to form an aluminium car body. For successful joining aluminium requires low heat input solutions. At present, self‐piercing rivets offer the best solution, but Jaguar engineers are looking at other processes including ultrasonic joining and friction stir spot welding. The aim is to find processes that are fast and cost‐effective. In the meantime, Jaguar will continue to use self‐piercing rivets for aluminium structures.

The practical implications of the work will lead to reduced cycle times which in turn will help to make the manufacture of aluminium car bodies more cost‐effective.

BMW claims it is the first car maker to make use of bowl‐feeding self‐piercing rivets for the manufacture of aluminium body‐in‐white.

The purpose of this study is to examine the effect of the rivet heads formed on the rivet strength by an experimental study if the bucking bar used in the forged rivet application includes gaps with different angles.

0.81 (0.032”) mm thick 2024 T3 sheets were used for the rivet joints. AD 2117 T4 forged rivets with a diameter of 3.2 mm (0.125″, 1/8″) are used for the joints. The special bucking bars (sidewall intersection angles of flat, 40°, 60° and 80°) were manufactured for the riveting process. To determine the mechanical properties of the prepared samples, cross-tension and tensile-shear tests were performed on a universal tensile testing machine.

As a result of the tensile-shear tests and cross-tensile, use of an 80 degrees bucking bar instead of rivets with a flat bucking bar increases the strength of the joint by approximately 20%. There is no systematic change in elongation. The results of tensile-shear and cross-tensile tests showed that forging rivets by special bucking bars have a significant effect on joint strength.

Increase in strength will require the use of thinner sheet metal and smaller rivets to achieve the same strength. This will reduce the weight of the aircraft. Weight reduction also means less fuel consumption and more economical flight. This increase in strength is a very important scientific achievement.

The purpose of this paper is to propose a computational approach in order to help establish the effect of various self-piercing rivet (SPR) process and material parameters on the quality and the mechanical performance of the resulting SPR joints.

Toward that end, a sequence of three distinct computational analyses is developed. These analyses include: (a) finite-element modeling and simulations of the SPR process; (b) determination of the mechanical properties of the resulting SPR joints through the use of three-dimensional, continuum finite-element-based numerical simulations of various mechanical tests performed on the SPR joints; and (c) determination, parameterization and validation of the constitutive relations for the simplified SPR connectors, using the results obtained in (b) and the available experimental results. The availability of such connectors is mandatory in large-scale computational analyses of whole-vehicle crash or even in simulations of vehicle component manufacturing, e.g. car-body electro-coat paint-baking process. In such simulations, explicit three-dimensional representation of all SPR joints is associated with a prohibitive computational cost.

It is found that the approach developed in the present work can be used, within an engineering optimization procedure, to adjust the SPR process and material parameters (design variables) in order to obtain a desired combination of the SPR-joint mechanical properties (objective function).

To the authors’ knowledge, the present work is the first public-domain report of the comprehensive modeling and simulations including: self-piercing process; virtual mechanical testing of the SPR joints; and derivation of the constitutive relations for the SPR connector elements.

Jaguar Cars has invested millions of dollars in two new facilities – a press shop and a body‐in‐white shop – to produce aluminium bodies for the next generation XJ luxury passenger car.

To review the capabilities of a new method of welding aluminium sheets for car body construction.

Describes the friction spot joining technique, and how it differs from friction stir welding. Describes the tests carried out at the University of Warwick to compare this with other aluminium sheet joining techniques.

Compared with resistance spot welding, this technique is simple, and physically and electromagnetically clean. Its low energy requirement per joint and low running costs give it advantages in joining thin materials, and eventual recycling is much easier than with self‐piercing riveting joints.

Describes the motivation behind the continuing development of an all‐aluminium joining technique, and compares spot friction joining with self‐pierce riveting and resistance spot welding.

Riveting deformation is inevitable because of local relatively large material flows and typical compliant parts assembly, which affect the final product dimensional quality and fatigue durability. However, traditional approaches are concentrated on elastic assembly variation simulation and do not consider the impact of local plastic deformation. This paper aims to present a successive calculation model to study the riveting deformation where local deformation is taken into consideration.

Based on the material constitutive model and friction coefficient obtained by experiments, an accurate three-dimensional finite element model was built primarily using ABAQUS and was verified by experiments. A successive calculation model of predicting riveting deformation was implemented by the Python and Matlab and was solved by the ABAQUS. Finally, three configuration experiments were conducted to evaluate the effectiveness of the model.

The model predicting results, obtained from two simple coupons and a wing panel, showed that it was a good compliant with the experimental results, and the riveting sequences had a significant effect on the distribution and magnitude of deformation.

The proposed model of predicting the deformation from riveting process was available in the early design stages, and some efficient suggestions for controlling deformation could be obtained.

A new predicting model of thin-walled sheet metal parts riveting deformation was presented to help the engineers to predict and control the assembly deformation more exactly.

Describes how Jaguar Cars in the UK is using robots to manufacture aluminium car bodies for its new XK sports car that is being built in the company's plant in Castle Bromwich, UK.

Describes the major production line techniques that are used in the manufacture of the body‐in‐white structure. These include self‐piercing rivets (SPRs), self‐tapping screws, MIG welding and adhesives.

The use of SPRs and self‐tapping screws are proving essential in the joining of aluminium components manufactured as extrusions, castings and pressings.

The introduction of SPRs and self‐tapping screws, adhesive bonding and MIG welding of cosmetic aluminium skin panels is the result of considerable research work on the part of Jaguar engineers and the company's suppliers, as well as Warwick University. Three of these techniques require the services of robots with their integrated controls. This work is likely to continue in order to reduce cycle times and improve overall product performance, both to the benefit of manufacturer and end‐user – the customer. This paper provides a unique insight into the development of a facility with islands of automation to produce aluminium body shells.

It is likely that arising out of development work into new techniques, processes and standards that will be used throughout the Ford organization, including other companies that form the Premier Automotive Group. Aston Martin, Land Rover and Volvo could all benefit from the technologies developed at Jaguar Cars.

This is the first time Jaguar Cars has used ABB robots in significant numbers to apply SPRs and self‐tapping screws to join aluminium components. ABB robots are also used for body shell inspection and MIG welding aluminum skin panels.

The automotive industry has been the principal driver in the development of robotics; however, as car design becomes more sophisticated, demands on robot makers will continue undiminished.

The riveting process is a metal forming process involving complex elastic-plastic deformation, which will induce a compressive residual stress field and cause local distortions in the connecting areas. Regarding to the aircraft panel assemblies with plenty of rivets, the global deformation is inevitable and undesired, leading difficulties to downstream assembly processes. This paper aims to present a new method for the local distortion calculation and the global deformation prediction of sheet panel assemblies during the automated riveting process.

In this paper, a simplified algebraic study is presented to analyze the local distortion of single countersunk rivet joint with the consideration of the barrel-like shape of the driven head and the through-thickness variations along the rivet shank. Then, an equivalent rivet unit is proposed based on the result of the algebraic study and embedded into the global-level model for the prediction of the overall distortions of riveted panels.

The algebraic study is able to reach a more precise contour of the deformed rivet than the traditional assumption of cylindrical deformations and rapidly determine the equivalent coefficients of the riveting unit. The result also shows an industrial acceptable accuracy of the prediction for the global deformations of the double-layered panel assemblies widely used in the aircraft panel structures.

A new local-global method for predicting the deformations of the riveted panel assembly based on the algebraic study of the local distortions is proposed to help the engineers in the early design stages or in the assembly process planning stage.