In the automobile, metallic components are increasingly being substituted by those made of plastic in order to achieve efficient lightweight construction and reduce CO2 emissions. The need to save weight exists both for vehicles with conventional internal combustion engines and for those with electric motor drives, as the weight saving in both variants ensures significantly lower rolling, acceleration and gradient resistance. Due to increasing component complexity, the plastic components used for this purpose can rarely be manufactured in one process step and must increasingly be welded. Both vehicles with conventional combustion engines and those powered by electric motors have identical requirements for component and weld seam quality. In addition to component tightness and high weld seam strength, this includes above all the temperature resistance of the materials, as these are exposed to high thermal loads in the automobile. Consequently, high-temperature resistant thermoplastics such as polyphtalamide (PPA) or polyphenylene sulphide (PPS) are increasingly being used.
Due to the high melting points of these thermoplastics, problems often occur in current series production with multi-stage welding processes as a result of the changeover process. The changeover process causes the previously heated joining zones to cool down. Furthermore, a high-strength, long-term joint connection of the individual components is the basic prerequisite for the use of components made of high-temperature thermoplastics in the automobile. However, a statement about the long-term properties of these materials is currently not possible, or only possible through time-consuming preliminary investigations. Therefore, a service life prediction model for welded high-temperature resistant components is to be developed within the scope of the project.