
194 Engineering Materials Technology
With hot extrusion the hot metal is forced, under pressure, to flow through a
die,
i.e. a shaped orifice (Figure 10.17). It is rather like squeezing toothpaste
out of its tube. Quite complex sections can be extruded.
Metal Die
Figure 10.17 Extrusion
10.4 Powder techniques
Shaped metal components can be produced from a metal powder. The process,
called sintering, involves compacting the power in a die, then heating to a
temperature high enough to knit together the particles in the powder.
Sintering of tungsten takes place at about 1600°C, considerably below the
melting point of
3410°C.
The sintering temperatur ...