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Tungsten and molybdenum are the two most widely used refractory metals. Both withstand high temperatures, but they differ significantly in density, melting point, conductivity and price. This comparison helps you pick the right metal for the job.
A short profile of each metal
Tungsten (W) has the highest melting point of all metals at around 3,422 °C and a very high density of about 19.25 g/cm³. Molybdenum (Mo) melts at around 2,623 °C and, at about 10.2 g/cm³, is only roughly half as heavy. Both are refractory metals: they keep their strength up to high temperatures and are processed under shielding gas or vacuum, as they oxidise in air when hot.
Density, melting point and temperature behaviour
Tungsten is the first choice wherever maximum temperature resistance or high density is required – as a high-temperature electrode, radiation source or shielding, for example. Molybdenum scores with better machinability and lower weight while still offering a very high melting point. For load-bearing high-temperature parts that are also mechanically stressed, the molybdenum alloy TZM is often the better choice (see separate guide).
Machining, cost and weight
Molybdenum is easier to machine than tungsten, which – due to its hardness and brittleness – is usually ground, EDM-cut or made near-net-shape by powder metallurgy. On weight, molybdenum wins when parts need to be light. Tungsten is generally more expensive and harder to source; where its special properties (density, melting point) are not strictly needed, molybdenum is often the more economical solution.
When tungsten, when molybdenum?
- Choose tungsten for: the highest service temperatures, radiation shielding, high density (balance weights, heavy metal) and TIG electrodes.
- Choose molybdenum for: furnace components, heat shields, electrodes in the glass and semiconductor industry, and parts with a good balance of temperature resistance, weight and machinability.
- We stock both as rods and semi-finished products — ex stock, in small quantities too, and cut to size.
Frequently asked questions
What is the main difference between tungsten and molybdenum?
Tungsten has the higher melting point (around 3,422 °C versus 2,623 °C) and almost twice the density (≈ 19.25 vs. ≈ 10.2 g/cm³). Molybdenum is lighter, easier to machine and usually cheaper.
Which metal conducts heat and electricity better?
Both conduct well. Molybdenum has slightly higher electrical conductivity, tungsten slightly higher thermal conductivity. In practice the choice is usually driven by temperature, density and machinability rather than conductivity alone.
Is molybdenum easier to machine than tungsten?
Yes. Molybdenum is more ductile and can be machined, whereas tungsten is usually ground or EDM-cut because of its hardness and brittleness.
What is each metal typically used for?
Tungsten: TIG electrodes, radiation shielding, balance weights and high-temperature electrodes. Molybdenum: furnace components, heat shields and electrodes for glass and semiconductor manufacturing.