摘要 |
Apparatus and process are described for producing predominately iron alloys that contain magnesium which alloys have particular utility for treating cast iron to form ductile and compacted graphite irons. The alloys are produced under pressure of an inert gas maintained above the vapor pressure of the magnesium at the melt temperature. The alloy melt is rapidly solidified in a chill mold which imparts a certain amount of constraint to the melt to provide a high magnesium recovery in the alloy and a clean, safe, economical operation. As a result of rapid solidification, the magnesium is retained in the alloy as a fine dispersion or separate phase which is of advantage for high magnesium recovery in the alloy and for a high magnesium recovery in the cast iron when treated with the alloys of the present invention. Any desired composition of alloy may be produced. Best results are obtained when the alloys contain by weight from about 0.5 to 4.0% magnesium and optionally from about 0.1 to 10% silicon, from about 0.5 to 6.5% carbon, from about 0.05 to about 2.0% cerium and/or other rare earth elements and from about 0.1 to about 10% nickel. One or more of the optional ingredients may be employed in the alloy of the present invention.
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