How is titanium sponge converted into titanium ingots?

The conversion of titanium sponge into ingots is primarily achieved through consolidation processes conducted in vacuum or inert gas environments to prevent contamination.12

Consumable-Electrode Arc-Melting

The most common method is the consumable-electrode arc-melting process.1
* Preparation: Titanium sponge, alloying elements, and sometimes recycled scrap are mechanically compacted and welded together to form a long, cylindrical electrode.1
* Melting: This electrode is melted vertically into a water-cooled copper crucible using an electric current.1
* Remelting: To ensure the uniform distribution of alloying elements, the resulting primary ingot is typically remelted at least once.1

Cold-Hearth Melting

An alternative method is cold-hearth melting, which is often used for recycling scrap that may contain high-density contaminants like carbide tool bits.1
* Process: The material is melted within a vacuum or argon chamber using electron-beam or plasma torches.1
* Separation: The molten metal flows horizontally over the lip of a water-cooled copper hearth, allowing high-density contaminants to settle at the bottom, effectively separating them from the purified metal before it enters the mold.1