Hard steel wire is generally made by forcing solid metal through a hole, called a die, under such intense pressure that it is extruded like pasta. Can you imagine the incredible forces that must be acting on the holes? In some cases diamond or sapphire (nearly as hard) dies are used, but this one is made of a tungsten alloy, probably because of its high strength even at very high temperatures.
On account of its prosperities of high heat resistance, good hardness, excellent plasticity ability, tungsten heavy alloy (WHA) is quite suitable material for tolls such as extrusion dies, die casting components, etc., especially when it is employed inextrusion die of copper related alloy, the manufacture of aluminum, zinc and brass castings.Tungsten alloy extrusion die applications made from a sintered material consisting of Mo and/or W containing 2-60% by volume of high melting point non-metallic components which are free from oxygen (except possibly in impurity amounts).
There is another property for tungsten alloy cylinder is durable, which guarantees its longer life than traditional die materials, and assure the minimum shrinkage porosity of die casting components. So the extrusion dies made of such raw material as tungsten are available with an assurance of high quality and standard.
Major advantages of tungsten alloy extrusion die and die casting components: high thermal stability, high impact resistance, good machinability, excellent crack resistance, reduction in press down-time, minimal extruded metal pick-up.