Slag

From GAWDAwiki

Slag is a vitreous or glass-like material containing oxides of materials such as manganese, silicon and aluminum. The slag produced solidifies on the surface of the weld, protecting it from atmospheric contamination as it cools and is removed later.^[1]

Components of Slag

Slag is typically made up of oxides of silicon, aluminum, and magnesium, as well as sulfur, which is always present. Slag also contains phosphorous, calcium, ash, and remnants of flux materials such as limestone.

Uses for Slag

While slag is a byproduct of welding and typically considered waste, it has many practical uses including:

• Concrete
• Aggregate road materials
• Ballast
• Phosphate fertilizer^[2]

References

1. http://www.bocindustrial.co.uk/bocindustrial/technical/glossary/a.asp
2. http://www.wisegeek.com/what-is-slag.htm