Joint between aluminium and thermoplast
Cross-section of joint between aluminium and thermoplast

Lighter cars with new joining methods

With legal requirements for reduced emissions and efforts to produce lighter cars, the automotive industry has to think along new lines. Volvo’s goal is to reduce the weight of their chassis by 60 kilos and is receiving help from Swerim to achieve this.

To reduce emissions vehicles must be lighter and more efficient. The methods for achieving this include using light materials such as fibre-reinforced polymer or aluminium.

New methods for hybrid joining

It must be possible however to combine the materials with existing materials in the chassis, but traditional joining methods perform poorly when the materials have different melting points, for example. New methods are now needed to join more difficult combinations of materials, so-called hybrid joining.

Swerim has studied various joining methods and among other things, assessed productivity and strength after joining. Researches have also studied the applications areas where the methods work best or adapted the methods for special applications. Several of the evaluated methods are already used by automakers, including for example Audi.

Right materials for a lighter product

The goal of Swerim’s work is to enable the use of combinations of materials in order to attain properties or weights that would otherwise be impossible to achieve. Lower chassis weights for cars make them more fuel efficient.

Volvo Cars is one of the companies that has participated in the project. Technical specialist Johnny Larsson explains that mixed material combinations will be necessary to further reduce chassis weights.

“Our goal for our next generation of cars calls for chassis that are 60 kilos lighter. To achieve this, we’ll base our designs on the relevant process and property data that has been produced in the various Swerim projects,” says Johnny Larsson.