Permanent mold casting of reactive melt

摘要

Titanium based and nickel based castings are made by casting a suitable melt having a relatively low melt superheat into a mold cavity defined by one or more low carbon steel or titanium mold members where the melt solidifies to form the desired casting. The melt super-heat is limited so as not to exceed about 150 degrees F. above the liquidus temperature of the particular melt being cast. For a steel mold, one or more titanium melt inlet-forming members are provided for cooperating with the steel mold members to form an melt ingate that communicates to the mold cavity for supplying the melt thereto in a manner to avoid harmful iron contamination of the melt during casting. The mold body-to-mold cavity volume ratio is controlled between 10:1 to 0.5:1 to minimize casting surface defects and mold wear/damage.