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Aluminum high-pressure die casting (HPDC) is used to reduce the cost and weight of various components in the automotive industry. The main problem with HPDC components is related to inherent flaws (porosity, oxide skins, etc.) that are difficult to avoid. The fatigue of aluminum HPDC parts is typically calculated using two S–N curves; one accounts for flaws in the bulk material and the other for the pore-free surface layer. This does not provide an accurate estimate for computation of the lifetime or safety against failure of the component. This paper presents a unique way to compute the fatigue safety factor taking into account the pore distribution of the component. The material model used is the so-called Kitagawa-Haigh diagram. The pore model provides a statistical distribution of pores within a defined region in the component.

This paper is concerned with the evaluation of the fatigue life and fracture mechanisms of a hypoid gear tooth root. The common milling manufacturing method for hypoid gear wheels is compared to the potentials of the innovative manufacturing method orbital forging. Extensive material and geometry analysis are performed and the local fatigue strength of the case hardened steel 18CrNiMo7-6 used in serial production is compared to the orbital forged and case hardened JIS steel SCM420H. Therefore a unique single contact engagement test procedure for hypoid gear wheels has been developed. The present investigations indicate a high potential for using orbital forging in the serial production. However, for an expected significant increase of the tooth root load carrying capacity due to the positive effects of forging (e.g. compressive residual stress, fiber orientation) and reaching the required geometry accuracy the process orbital forging has to be optimized in further steps.

An automated assessment of structures with welding seams or spot joints is presented. Based on guidelines and with the help of software-coded procedures, the Finite Element model is conventionally build up including welding seams and spot joints. After having determined the stresses by linear or geometric nonlinear Finite Element analyses (FEA), the stresses are post-processed by a software package taking into account the special properties of the welding seams and the spot joints as defined in the FE-model. With it, the fatigue life, in terms of safety factor or damage distributions, can be evaluated fast and efficiently and may be displayed on the FE-structure. Computationally optimized welded or spot-jointed structures become feasible with this software package, leading to development time and cost reductions due to minimizing testing expenditures.

Requirements for constant track and camber have a much greater priority with commercial vehicles than on passenger cars. The target can be reached by a concept of rigid wheel suspension elements. It may cause some problems due to structural noise (vibration transfer). However, on commercial vehicles with elastic suspended driver cabs the noise transfer problem is considered to be manageable by suitable cab suspension elements, on buses a compromise in the tuning has to be found regarding overall damping.

This paper presents a simulation tool for the design of cooling systems. The simulation tool can consider the cooling air circuits as well as the coolant circuits. This is a development of the simulation process representing the realization of a planned step towards simulating the vehicle and its whole engine. The flow models of both the cooling air and the coolant are based on Network Flow Theory which permits the construction of complex cooling circuits. The aim of the simulation analysis, in addition to the operational reliability of the cooling system, is the energy optimization of the whole system. Using the simulation analysis, power consumption by the fans, radiator and oil pump can be minimized. At the same time the cooling system has to be designed so that the temperatures are favorable for lubricants and fuels in all driving conditions.