Metal · Material guide
Get quotes for custom molybdenum parts
Molybdenum is a refractory metal with a melting point above 2600°C, high thermal conductivity, and a very low coefficient of thermal expansion, which is why it shows up in semiconductor equipment, vacuum furnaces, and glass-melt hardware. Only shops set up for refractory metals should run it. Upload your drawing and we'll source quotes from qualified partners.
STEP · STL · IGES · DWG · DXF · PDF · and more
Uploads are secure & confidential
Grades
Molybdenum grades shops run most
The grade sets temperature capability, strength retention, and ductility. These are the ones to specify by name.
Molybdenum 99.95% (pure Mo)
Standard commercial-pure molybdenum, 99.95% minimum, available as plate, sheet, rod, and bar from Plansee, H.C. Starck, Edgetech, and Elmet. Excellent thermal and electrical conductivity, poor machinability but routine for refractory shops with the right tooling.
Best for Furnace hot-zone hardware, sputter-target backing plates, glass-melt electrodes, X-ray anodes
TZM (Mo-0.5Ti-0.08Zr-0.03C)
Titanium-zirconium-molybdenum alloy that keeps most of pure moly's conductivity while roughly doubling strength and extending the useful temperature range. Preferred for stressed hot-zone parts and tooling that would creep in pure Mo.
Best for Hot-zone tooling, aerospace propulsion test hardware, high-temperature fasteners, crystal-growth furnaces
MHC (Mo-Hf-C)
Hafnium-carbide-strengthened moly for the highest service temperatures where TZM runs out. Rare in general supply chains; typically a specialty order through the same refractory mills.
Best for Extreme hot-zone components, specialty aerospace, research reactors
Mo-La (lanthanated)
Molybdenum doped with lanthanum oxide for better ductility and resistance to recrystallization at high temperatures. Used where pure moly would embrittle on thermal cycling.
Best for Lamp electrodes, high-cycle thermal components, lighting and optics
Specs
Material properties
Representative values for 99.95% pure molybdenum. TZM and MHC retain strength further into the high-temperature range.
| Property | Typical value |
|---|---|
| Density | 10.22 g/cm³ (0.369 lb/in³) |
| Melting point | 2623 °C (4753 °F) |
| Tensile strength (annealed) | ~85 ksi |
| Yield strength (annealed) | ~70 ksi |
| Hardness (annealed) | ~160 HV |
| Coefficient of thermal expansion | ~4.8 µm/m·K (near silicon, which is why it is used in semi) |
| Thermal conductivity | ~138 W/m·K |
| Electrical resistivity | ~5.2 µΩ·cm |
| Machinability | Poor; carbide tools, rigid setups, sharp geometry required |
| Ductile-to-brittle transition | ~30 °C — avoid cold working below room temperature |
Molybdenum oxidizes aggressively above about 400 °C in air. Service is almost always in vacuum, inert atmosphere, or reducing conditions. Note the atmosphere on your drawing.
Stock
Forms we machine it from
Plate & block
Sputter-target backing plates, furnace crucibles, heat sinks.
Round bar & rod
Electrodes, fasteners, machined rotational parts.
Sheet & foil
Heat shields, lamp parts, thin heat spreaders.
Processes
Manufacturing methods for molybdenum
The right process depends on part geometry, tolerances, and production volume.
Finishing
Finishes for molybdenum
Molybdenum is usually left machined or polished. Coatings are specified when service exceeds oxidation threshold or when a specific electrical surface is required.
As-machined
Standard for vacuum and inert-atmosphere service. Minimal post-processing.
Chemically cleaned & etched
Removes machining contaminants and residual oxide for high-purity semi and vacuum work.
Polished
Mirror or near-mirror finish for sputter-target backing and optical hot-zone parts.
MoSi2 or oxidation-resistant coating
Molybdenum disilicide and similar coatings for service in air above 400 °C.
Plated (gold, nickel)
Thin plating on electrodes and contacts for specific electrical requirements.
Fume and dust from grinding, EDM, and welding Mo (and especially MoO₃) are documented health hazards. Shops quoting Mo should state their ventilation and PPE protocol; we only route moly RFQs to shops that confirm they are set up for it.
Applications
Where molybdenum parts are used
Molybdenum shows up where temperature or thermal expansion is the hard constraint, and where no cheaper alternative works.
Compare
Molybdenum vs other materials
How molybdenum stacks up against the alternatives for high-temperature and specialty parts.
Molybdenum vs Tungsten
- Tungsten has a higher melting point (3422 °C) and higher density (19.3 g/cm³)
- Molybdenum machines (relatively) better and costs less than tungsten per pound
- Both oxidize above a few hundred °C and need inert or vacuum service
Choose tungsten for the highest temperatures or where density is a feature (shielding, counterweights). Choose Mo for most hot-zone and semi work.
Molybdenum vs TZM
- TZM keeps strength further into the high-temperature range than pure Mo
- TZM resists creep much better in loaded hot-zone parts
- Pure Mo has slightly higher thermal and electrical conductivity
Choose TZM when the part sees high mechanical stress at temperature. Choose pure Mo for conductivity-driven parts and lightly loaded fixtures.
Molybdenum vs Inconel 625/718
Inconel 625/718 →- Inconel is readily machinable and cheaper, but tops out around 980 °C service
- Molybdenum keeps strength and dimensional stability well above where Inconel softens
- Inconel oxidizes safely in air; moly does not
Choose Inconel when temperature is below ~980 °C and air service is required. Choose moly above that or when CTE match to silicon matters.
Questions
Frequently asked questions
Its coefficient of thermal expansion (~4.8 µm/m·K) is close to silicon, so a moly fixture or sputter backing plate expands at nearly the same rate as the wafer or target through heat cycles. That keeps bonds intact and wafers flat. It also conducts heat well and tolerates vacuum, which are the other requirements for process equipment.
More materials
Other materials on OpenSpindle
Need molybdenum or TZM parts machined?
Upload a drawing and we route it to refractory-metal shops with the equipment, PPE protocol, and mill sourcing to run moly. Quantity one is quoted seriously; realistic 3–6 week lead times built in.
STEP · STL · IGES · DWG · DXF · PDF · and more
Uploads are secure & confidential