In this contribution Audi describes how, in future, the lightweight material magnesium can be used in engines subject to extreme loads if special detail design solutions and new creep-resistant alloys are adopted. To compensate for the drawbacks of magnesium, AUDI has developed a new crankcase concept in which the magnesium structure is reinforced by local material engineering in critical areas. The result of this development is a compact, multi-functional cylinder insert made of aluminium which is incorporated into the magnesium block using a pressure die-casting process. It combines the typical functions of an engine block, namely cylinder bores, threads for mounting the cylinder head, threads for the main bearing caps and a water jacket (for engine cooling). The special feature of this engineering concept is that both open-deck and closed-deck engine blocks for high peak pressures can be produced by die-casting. So far this advantage has only been available with sand cast or gravity die-cast engine blocks.
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