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This paper describes the research activities founded by the European Commission under the 5th Frame Work Programme, titled “Lighter and Safer Automotive 3D-Structures at Low Investments through the Development of the Innovative Double Sheets Hydroforming Technology”. As described into the project title, the objective is to develop and optimise double sheets hydroforming (DSH) in order to manufacture 3D automotive structures. A moch-up, representative of an automotive side frame, was designed both to evaluate the process limits and to validate the developed methodology for process numerical simulation. Design guidelines for application of this technology are the final output of the project. After a general overview description of the European project and its objectives, the following points will be described: mock-up design; process numerical simulation; experimental results.

A new category of hypereutectic aluminum liners, made by PM route is now available on the market (SILITEC) and it is successfully applied to high-pressure die casting process to produce open deck cylinder blocks. The claimed achievable engine performances over cast-iron liners (weight saving, reduction of oil consumption, optimal heat transfer, wear and friction losses reduction) justify the interest of automotive industry in developing such a technology. The paper will present the experience and the achieved results in permanent mold gravity casting with Silitec liners, where metal flow definition and temperature distribution control make the casting technique more challenging for the manufacturing of closed deck cylinder blocks.

Aluminum foams properties, as energy absorbing materials, were experimentally studied. Having as objective the improvement of the vehicle crashworthiness, two different applications were considered. as a filler material for hollow components of the body frame; in this case the objective is to reinforce weak areas of the frame for a better control of the collapse during the crash; as a material to be employed for the manufacturing of energy absorbing structures for the crashworthiness improvement at low speed impact. Some prototypes were manufactured and tested in order to evaluate the potential benefits for both the applications. Good results obtained in both cases pointed out Al-foam as promising material for increasing the passive safety of the vehicle.

An optimisation analysis on an aluminium matrix composites brake drum was carried out in order to obtain a greatly lighter component with equal or better performances than the traditional one. For this reason, a FEM numerical model, fitted on the basis of experimental data, was developed to optimise the design of a brake component in order to meet the required targets; moreover, dynamometer testing allowed to point out the guidelines for the design optimisation. The redesigned MMC drum showed good results, allowing a component weight saving up to 50%.