How does cold-hearth melting help remove contaminants from titanium scrap?

Cold-hearth melting is a specialized consolidation process used to purify titanium scrap by leveraging the physical properties of contaminants. Conducted within a vacuum or argon chamber, the process uses electron-beam or plasma torches to melt the metal in a horizontal, water-cooled copper crucible.1

As the molten titanium flows along this horizontal path, high-density contaminants—such as carbide tool bits often found in recycled scrap—are effectively removed because they settle to the bottom of the hearth rather than flowing into the mold. This method is particularly valuable for recycling, as it ensures that dense impurities are separated from the purified metal before it is cast into a final ingot.1