Hot extrusion lubricants
• Molten glass is the most common lubricant for steel and nickel
based alloys (high temp extrusion).
The billet is heated in an inert atmosphere and coated with glass
powder before being pressed.
• This glass coating is soften during extrusion to provide a lubricant
film (~25 µm thick), which serves not only as a lubricant but also a
thermal insulator to reduce heat loss to the tools.
• Graphite-based lubricants are also be used at high extrusion
temperature.
• MoS2