Yttrium as a Nodulizer for Cast Iron

摘要

Yttrium metal in varying amounts was added to experimental laboratory heats of cast iron to study operating procedures and related problems involved in its use as a nodulizer. Approximately 0.20 to 0.25 percent yttrium added to the charge produced the most satisfactory microstructure and mechanical properties. Nodular iron made with yttrium has mechanical properties similar to nodular iron made with magnesium. However, the present price of yttrium makes it economically unsound to use for foundry production castings. Materials such as silicon and nickel alloyed with yttrium did not improve the nodulizing efficiency. Superheating the molten bath before adding the yttrium improved the mechanical properties. (Author)