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In large-scale industrial simulations the numerical prediction of fracture in sheet metal forming operations as well as in crash events is still a challenging task of high social and economic relevance. Among several approaches presented in literature, the authors and their colleagues developed a model which accounts each for three different mechanisms leading finally to fracture in thin sheet metals: the local instability (necking), ductile normal fracture and ductile shear fracture. The focus of this paper is to develop and validate a new approach to improve the predictive capabilities for fracture triggered by localized necking for a wide variety of steel grades. It is well known that after the onset of a local instability additional strain is still necessary to induce fracture. In a numerical simulation using shell elements this post instability strain becomes of increasing importance when the ratio of the characteristic shell element edge length to its thickness decreases.

Efficiency and dynamic behavior of a vehicle are strongly affected by its weight. Taking into consideration comfort, safety and emissions in modern automobiles, lightweight design is more of a challenge than ever in automotive engineering. Materials development plays an important role against this background, since significant weight decrease is made possible through the substitution of high density materials and more precise adjustment of material parameters to the functional requirements of components. Reinforced light metals, therefore, offer a promising approach due to their high strength to weight ratio. The paper gives an overview on matrix and reinforcement structures suited for the high volume output of the automotive industry. Further analytical and numerical approaches to describe the strengthening effects and the good mechanical characteristics of these composite materials are presented.

The validity of numerical simulations is still limited by the unknown failure of materials when nonlinear load paths in successive stamping and crash processes occur. Localized necking is the main mechanism for fractures in ductile sheet metal. The classical forming limit curve (FLC) is limited to linear strain paths. To include the effects of nonlinear strain paths a theoretical model for instability (algorithm CRACH) has been used. The algorithm has been developed on the basis of the Marciniak model [8]. The calibration and validation of this approach is done by a set of multistage experiments under static and dynamic strain rates for a mild steel.

Over the past 30 years, the computer-aided engineering (CAE) tools have been applied extensively in the automotive industry. In order to accelerate time-to-market while coping with legal limits that have become increasingly restrictive over the last decades, CAE has become an indispensable tool covering all major fields in a modern automotive product design process. However, when tackling complex real-life engineering problems, the computational models might become rather involved and thus less efficient. Therefore, the overall trend in the automotive industry is currently heading towards combined approaches, which allow the best of the both worlds, namely the experimental measurement and numerical simulation, to be merged into one integrated scheme. In this paper, the so-called patch transfer function (PTF) approach is adopted to solve coupled vibro-acoustic problems. In the PTF scheme, the interfaces between fluid and structure are discretised in terms of patches.

Modern automotive engineering is more than ever affected by a multitude of different and sometimes contradictory requirements. Innovative materials play an increasingly important role in ensuring the fulfillment of these requirements. Conventional material development has always met these demands to a high standard. However, there will be challenges where nanotechnology will provide us with even more intelligent solutions. Consequently, automotive engineering makes more and more use of the large variety of new technological functionalities and innovative applications offered by nanotechnology. Nanotechnology involves property changes that only occur at the nanoscale. Some selected properties are suitable to be used in the design of tailored materials called nanomaterials, opening up a new dimension in automotive engineering. Nanomaterials promise valuable progress through new functionalities, in particular safety and quality rating applications or lightweight construction.

Despite increasingly stringent crash requirements, the body structures of future mainstream production cars need to get lighter. Carbon fiber reinforced polymer (CFRP) composites with a density 1/5th of steel and very high specific energy absorption represent a material technology where substantial mass can be saved when compared to traditional steel applications. BMW have addressed the demanding challenges of producing several hundred composite Body-in-White (BIW) assemblies a day and are committed to significant adoption of composites in future vehicle platforms, as demonstrated in the upcoming i3 and i8 models. A next step to further integrate composites into passenger cars is for primary structural members, which also perform critical roles in passive safety by absorbing large amounts of energy during a crash event.

Reductions of hardware costs as well as implementations of new innovative functions are the main drivers of today's automotive electronics. Indeed more and more resources are spent on adapting existing solutions to different environments. At the same time, due to the increasing number of networked components, a level of complexity has been reached which is difficult to handle using traditional development processes. The automotive industry addresses this problem through a paradigm shift from a hardware-, component-driven to a requirement- and function-driven development process, and a stringent standardization of infrastructure elements. One central standardization initiative is the AUTomotive Open System ARchitecture (AUTOSAR). AUTOSAR was founded in 2003 by major OEMs and Tier1 suppliers and now includes a large number of automotive, electronics, semiconductor, hard- and software companies.

This paper presents new aspects of the casting and manufacturing of BMWs inline six-cylinder engine. This new spark-ignition engine is the realization of the BMW concept of efficient dynamics at high technological level. For the first time in the history of modern engine design, a water-cooled crankcase is manufactured by magnesium casting for mass production. This extraordinary combination of magnesium and aluminium is a milestone in engine construction and took place at the light-metal foundry at BMW's Landshut plant. This paper gives a close summary about process development, the constructive structure, and the manufacturing and testing processes.