The Recrystallization temperature is the temperature at which the grains in the materials are replaced by a new set of grains. Different materials have different recrystalliztion temperature. Materials above the recrystallization temperature have high ductility and lesser strength and hardness.
Hot Extrusion is done with metals and alloys. Glass powder is used as a lubricant between the metal and the extrusion machine.
Examples of components that are hot extruded are railings, automotive components, pipes,and frame members.