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Modern automobile diesel engines make use of aluminium cylinder heads that experience both high pressure and thermal loads. Maximum temperatures are above 250°C in the valve bridge area, generating microstructural transformations in the material and thus local evolution of the mechanical properties. To be able to predict the life time of this component with a reasonable amount of confidence, it is therefore necessary to describe these changes in the material. This has been done on a variety of casting materials, with various amount of silicon and copper. Two of them have been taken as references, namely the A356 and 319 type of alloys, making extensive use of Transmission Electron Microscope (TEM) associated with Automatic Image Analysis for quantitative analysis of the precipitation stages during different heat treatments, from the as-received state to saturated aging state.

The A 390 (18% silicon, 1% copper Aluminum alloy) and a new designed friction material which could have a potential use in brake application have been studied on a pad-on-disk tribometer, where the pad was made of the friction material and the disk out of the hypereutectic alloy. An experimental study has allowed to optimize the formulation of the pad and the heat treatment of the disk material in order to get the best wear-properties (low wear, stable friction coefficient). Analysis have been used to understand the wear mechanisms, i.e. microstructural evolution and degradation of the material.

Modern architectures for diesel cylinder heads, especially high performance, direct injection heads for passenger cars and light trucks, require an optimized combination of design and material properties. In aluminium castings, microstructural gradients and associated fatigue and mechanical properties can result from the process selection, e. g. gravity or low pressure, and from the variable cooling rates which have to be applied to the different parts of the casting in order to get a progressive solidification and a sound part. It is thus essential to understand the relationship between the microstructure resulting from the combination of process, material choice and heat treatment, and the properties of the material. As the most widely used material for aluminium diesel as well as gasoline cylinder heads, the 319 alloy has been selected for its superior strength. We have carried out tensile testing and thermo - mechanical fatigue testing on a range of materials.

Total automotive paint systems generally include three different coating layers: a cataphoretic primer, a sealer, and a top coat. The top coat gives the final aesthetic to the system, and the cataphoretic primer is supposed to be the ultimate protective layer against corrosion as well as the adhesion promoter, being directly in contact with the metal (or with the surface-treated metal). For this reason, it is very important to control the diffusion rate, through the cataphoretic primer, of poisonous species such as chloride or cathodic delamination initiators; i. e. oxygen and water. Although numerous studies have been reported on the corrosion mechanisms affecting automotive body panels, (either primer coated or fully painted), little has been done with regard to the transportation properties of the different paint layers concerning species such as oxygen and water vapour that are usually considered to be rate determining in the degradation of those systems.