Metallgesellschaft Aktiengesellschaft

Skw Trostberg Aktiengesellschaft

Karl J Reifferscheid

Friedrich Wolfsgruber

Werner Gmohling

Ernst A Weiser

Dieter H Gumbinger

Ernst J Doliwa

Heiner Trager

Hans Kern

Karl-Heinz Kleemann

In a process of producing nodular cast iron wherein molten cast iron is treated in two stages with elements for inducing a formation of a predominantly nodular graphite, the crystallization of the graphite and the dynamic properties of the casting are improved in that a rare earth metal is added to the molten cast iron in the first treating stage and magnesium metal or a magnesium-containing master alloy in an amount which is sufficient for the formation of a predominantly nodular graphite is added to the molten cast iron in the second treating stage, in which no RE metal is added to the molten cast iron. The treatment is particularly effected with sheathed wires consisting of a steel sheath around a core of treating agent powder.

Method of producing nodular cast iron

A process is described in which cast iron melt are inoculated in the mold. The cast iron melt flowing through the sprue or gate system of the mold is contacted in the mold with an inoculate body that is contained in the mold. In order to increase the rate of dissolution and to improve the results of inoculation, said body is mounted at both ends in mutually opposite recesses (core prints) in the wall of the sprue or gate system. In another embodiment, the flow area is constricted closely below the inoculating body.

Process and apparatus for inoculating cast iron

The present invention provides a treatment agent for cast iron melts based upon ferrosilicon magnesium with a silicon content of from 40 to 80% by weight and a magnesium content of from 0.5 to 15% by weight, said agent being in the form of granules with a specific surface area of from 0.2 to 0.8 m.sup.2 /g. according to BET. The present invention also provides a process for the production of this treatment agent, wherein a jet of molten ferrosilicon magnesium alloy is directed on to a bounce plate made of fire-resistant material and the melt droplets which bounce back from bounce plate are allowed to solidify in a liquid-filled collection receiver.

Treatment agent for cast iron melts and a process for the production

It is known to contact molten cast iron with various treating agents in the casting mold in order to influence the base structure or the form of the graphite. Such casting molds for making castings of cast iron containing vermicular and/or spheroidal graphite are provided with an intermediate chamber, which is provided in the pouring system between the pouring gate and the ingate to the casting mold proper. That intermediate chamber serves to receive the graphitizing agent and to contact it with the molten cast iron. To permit a functional adaptation of the chamber surface area or the surface area of the treating agent contained in the chamber to the pouring gate, which changes as the pouring proceeds, the casting mold is provided with a frustopyramidal intermediate chamber which has a rectangular base disposed in the parting plane of the mold.

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Karben, Germany

Karl J Reifferscheid