Gradient cast

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The Gradientenguss is a casting in the form of foundries .

The name is derived from the term temperature gradient , which serves as a measure for the cooling of a melt in the casting mold. Different temperature gradients also result for two different melts. This makes it possible that a melt with a faster cooling in the casting mold, i.e. a high temperature gradient, first solidifies at certain points of the mold to such an extent that it can be poured over or around a melt of a different composition. Where the melts meet, they form connecting intermetallic phases that consist of elements from both melts.

Areas of application

The process is used both in iron foundries, when using cast iron melts that solidify at different rates due to their graphite formation, and in light metal castings, primarily in the manufacture of engine blocks and in this case is intended to lead to weight savings. A corresponding shaping - usually there are sand molds - enables the casting of certain areas of the mold with aluminum - alloy , the other with a magnesium alloy. The aluminum alloy is fed to the particularly stressed parts of the engine block, such as the cylinder walls. Parts used purely for the external shaping are filled with the magnesium alloy while saving weight.

Weight saving is also the goal with hybrid casting, only here already finished parts of the future casting, mostly thermally particularly stressed, are inserted into the mold as “inserts” and then cast around with a magnesium alloy. This is of practical relevance in the manufacture of crankcases for automobile engines.

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