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Looking for car weight reduction related to the use of High Strength Steels (HSS) for manufacturing body-in-white components, an innovative application of the high velocity forming techniques has been developed: the Electro Magnetic (EM) calibration and elimination of the spring-back effect (sidewall curl) of High Strength Steel U-channels. Within this paper the initial tests on L and U-shaped parts will be presented. Being the mechanical stiffness the main parameter for improving the coil endurance, the prediction of the coil strains under EM forces is a basic issue, which has been addressed within this study.

The need to reduce weight of large and heavy components used by the automotive and aerospace industries such as engine block, cylinder head cover and helicopter gearbox housing has led to the development of new Mg gravity casting alloys that provide adequate properties and cost effective solution. The new Mg gravity casting alloys are designed for high stressed components that operate at a temperature up to 300°C. These new alloys exhibit excellent mechanical properties and creep resistance in T-6 conditions. The present paper aims at introducing three new Mg gravity casting alloys designated MRI 201S, MRI 202S and MRI 203S, which were recently developed by the Magnesium Research Institute of DSM and VW. Apart from the excellent high temperature performance of these alloys, they provide adequate castability and dimension stability along with good weldability and corrosion resistance.

State of the art demonstrates that weight of vehicle increases with length of car body. Integration of powertrain in mid rear underfloor location enables to shorten car body by more than 0,5m and to save partially heavy longitudinal members. Underfloor integration of power train induces higher stance floor for more conviviality of passengers visibility. Safety factors are improved by lowering gravity centre, better repartition of front / rear masses during braking, easier management of crash by straighter and higher front longitudinal members and free front space. Space frame architecture simplifies light weight technologies application by using 2D bended aluminum profiles. Low investment is ensured by minimising castings application to suspension attachments and interlinking upperbody to underbody. Floor and external panels are designed for aluminum sheet stampings.

A specific objective of the European Mg-Engine project is to qualify at least two die cast Mg alloys with improved high temperature properties, in addition to satisfactory corrosion resistance, castability and costs. This paper discusses the selection criteria for high temperature alloys leading to four candidate alloys, AJ52A, AJ62A, AE44 and AE35. Tensile-, creep- and fatigue testing of standard die cast test specimens at different temperatures and conditions have led to a very large amount of material property data. Numerous examples are given to underline the potential for these alloys in high temperature automotive applications. The subsequent use of the basic property data in material models for design of automotive components is illustrated.

Eight partners from Europe and one from North America have joined efforts in a EU-supported project to find new ways for sustainable production of Mg-based engine blocks for cars. The ultimate aim of the work is to reduce vehicle weight, thereby reducing fuel consumption and CO2 emissions from operation of the vehicle. Four new magnesium alloys are considered in the project and an engine block has been series cast - 20 each in two alloys. An extensive mechanical testing program has been initiated to identify in particular the high temperature limits of the four alloys and a significant experimental study of proper bolt materials for joining is being done in parallel. Engine redesign and life cycle analysis has also been completed to secure the future sustainable exploitation of the project results. This paper presents an overview of the work and results obtained until now - 3 months before the ending date of the project.

Recently several new magnesium alloys for high temperature applications have been developed with the aim to obtain an optimal combination of die castability, creep resistance, mechanical properties, corrosion performance and affordable cost. Unfortunately, it is very difficult to achieve an adequate combination of properties and in fact, most of the new alloys can only partially meet the required performance and cost. This paper aims at evaluating the current status of the newly developed alloys for powertrain applications. The paper also addresses the complexity of magnesium alloy development and illustrates the effect of alloying elements on properties and cost. In addition, the paper presents an attempt to set the position of each alloy in the integrated space of combined properties and cost

The growing demand for the use of magnesium alloys in the production of automotive powertrain components led to the development of creep resistant diecasting alloys MRI153M and MRI230D. The present paper addresses the main high-pressure die casting parameters, which significantly affect the performance of components, produced of these new alloys. A systematic study was carried out in order to correlate die-casting parameters to the performance of new alloys. The results obtained clearly indicated that optimization of molten metal and die temperatures, injection profile parameters and lubrication mixtures allowed to improve the die castability and service properties of the new alloys and produce high performance components with intricate geometry. This was manifested by production of several practical demonstrators such as gearboxes, oil pans, oil pumps and crankcases.

The hatchback of Volkswagen's 3 liter car (3 l fuel consumption per 100 km) consists of an inner component of die casting magnesium (AM50) covered with an aluminum panel from the outside. This hybrid design requires a new manufacturing process: The pre-coated magnesium part will be bonded and folded with the bare aluminum part. Corrosion protection is provided by an organic coating system which both protects against general corrosion and galvanic corrosion. The corrosion of the Al / Mg sandwich has been examined with hybrid samples which are similar to the hatchback. Several powder coatings (epoxy resin, polyester resin, hybrid resin), wet paints and cathodic electro-coating paints of different thicknesses and compositions have been applied to the magnesium part. They show that only powder coating provides adequate protection. Galvanic corrosion at the points of attachment of the hatchback might be possible (for example the bolted joint of the hinge).

Crank-angle resolved, gas temperatures are determined in the combustion chamber of a Volkswagen (VW) standard-production, port-injected SI engine. During idle, two different methods are applied: (1) a direct spectroscopic emission-absorption technique at a resonance line of potassium, seeded to the air stream to generate sufficient spectral absorptance (‘colouring’ technique), and (2) a more standard, indirect method in which temperatures are derived from pressure recordings using a two-zone thermodynamic model. Combustion temperatures obtained during idle with both the spectroscopic (1) and ‘two-zone’ (2) methods are in good agreement. In addition, the spectroscopic technique is extended to transient operating conditions where the ‘two-zone’ method is not applicable. Combustion temperatures measured during cold-start and abrupt load alteration are in good agreement with former investigations.