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Tungsten's melting point of 3422 °C is the highest of all metals and second only to carbon (3550 °C) among the elements. This is why tungsten is used in rocket nozzles and reactor linings. There are refractory ceramics and alloys that have higher melting points, notably
Ta
4
HfC
5
TaX4HfCX5
with a melting point of 4215 °C, hafnium carbide at 3900 °C and tantalum carbide at 3800 °C.
Carbon cannot be used to hold molten tungsten because they will react to form tungsten carbide. Sometimes ladles and crucibles used to prepare or transport high melting point materials like tungsten are lined with the various higher melting ceramics or alloys. More typically tungsten and other refractory materials are fabricated in a non-molten state. A process known as powder metallurgy is used. This process uses 4 basic steps: