Over recent decades, cars have become larger and heavier with every new generation. The main drivers of such a weight increase have been the improved safety and comfort requirements. Decades of R&D investments to tackle this tendency have resulted in a substantial increase in the weight-specific performance of components and assemblies in terms of cost, strength and stiffness. However, the need for weight reduction in future electric vehicles, without unduly compromising performance and safety, is even stronger since additional weight translates into either reduced driving range or in larger, heavier and more expensive batteries. Within this context, the European Green Vehicle project ENLIGHT developed highly innovative lightweight material technologies for application in structural vehicle parts of future volume produced electric vehicles. Among others, ENLIGHT developed thermoplastic matrix composite and associated manufacturing technologies to a stage that they were applicable at least in medium volume production. The material development was complemented by investigating the required manufacturing and assembly technologies as well. In this paper, a summary of the major results obtained during the four-year project year is presented. A special focus is given to a semi-active composite control arm with significant reduced weight but enhanced NVH properties.

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The number of laser welded applications in industry is rising steadily. For example, laser welding of polymers is used in the automotive, household and medical sectors. In these areas, a high focus on long-term durability and reliability of laser welds is required. The laser welds are exposed to several types of loading, such as ambient conditions, variable amplitude loading and multiaxial loading. Multiaxial loading causes a multiaxial stress state in the laser weld line. However, the determination of such multiaxial stress states presents a challenge. The interactions of different types of loading, such as tension, torsion and in or out of plane loading, especially for cyclic loading, have not yet been examined comprehensively. Test specimens for determining the influence of such parameters on long-term durability of laser welds are not widely available. This paper presents the results for multiaxial loading on thermoplastic laser welds. Therefore, the MultiWeldTester is used

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At the present time, the amount of polymers used for lightweight design applications is increasing steadily. In the past, components made from polymers have often been designed using conventional structural design concepts. These concepts do not scope all of the potential benefits of the material which could be used for lightweight design. A new technology for the joining of polymers used for lightweight structures is the laser welding process. For structures joined using this new technology, the specific values of mechanical properties of the polymer weld lines, which are essential for lifetime estimation, are often missing. In most instances, the requirement is for laser welded structural components to be hermetically sealed. Therefore, inner pressure testing is an allocated test scenario. Test specimens that can be used to represent specific inner pressure load scenarios are only partially available. This paper presents a new type of test specimen for inner pressure loading at the laser weld line. Based on experiments, S/N-curves for inner pressure loading and different laser weld process applications have been established