Fast-moving machine tool assemblies should be light and rigid. Because of the lightweight construction and the dynamic loads these assemblies are very often susceptible to vibrations. Aluminum foam sandwiches are laminates with an aluminum foam core and compact cover sheets. The foam cores possess a high-energy absorption capacity. Machine tool assemblies made of aluminum foam sandwiches offer very high flexural stiffness, together with comparatively light weight. Vibrations generated by machining are damped very well due to the cellular structure of foam. The manufacturing process of foam sandwiches is in general well understood, but there are still some open questions concerning the mechanisms of bonding and adhesion between cover sheets and foam core. This paper tries to give answers to these questions

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The manufacturing processes for sandwiches made with aluminum or steel sheets are differentiated by their various melting ranges. Sandwiches with aluminum face sheets have recently been produced using to the so-called AFS technology, which includes a rolling process. However, if it is desirable to avoid rolling to reduce costs and allow for quick and flexible responses to the needs of the customer, the manufacturing process must be redesigned.

In the past it could be proven that aluminium foam is a construction material appropriate for numerous applications. The widespread use of aluminium is still hampered by the high production costs resulting on the one hand from the costly production method, and on the other one from expensive starting materials. The present work focuses on studies on alternative, cheaper starting materials. The results presented in this work support the idea that aluminium chips may be successfully used as base material instead of atomised powders. It could also be proven that good foaming rates can be achieved with calcium carbonate as foaming agent for aluminium

KurzfassungDas Ziel der Untersuchungen bestand in der Erarbeitung grundlegender Erkenntnisse über mikrostrukturelle Veränderungen im technologischen Prozessablauf der Metallschaumherstellung nach dem schmelz-pulvermetal-lurgischen Verfahren. Dazu war eine exakte Gefügecharakterisierung in allen technologischen Stufen notwendig. Übliche metallografische Präparationen waren wegen der leicht flüchtigen Komponenten der Treibmittel sowie der locker gepressten Pulver mit entgegengesetzten Eigenschaften nicht realisierbar. Mit dieser Arbeit wurden Möglichkeiten der Ionenstrahlpräparation erarbeitet, mit denen die Gefüge und insbesondere das Treibmittel in allen technologischen Stufen (Pulvermischung, Blöcke, Stränge, Metallschaum) exakt dargestellt werden konnten.