Metal powders · WC
Tungsten Carbide Powder (WC)
Carburised WC powder in four Fisher grain-size grades for cemented carbide production, diamond segments and wear-resistant tooling, with carbon balance controlled lot by lot.
About Tungsten carbide powder
Tungsten carbide powder is produced by carburising tungsten metal powder with carbon black at high temperature. The whole quality argument for WC comes down to the carbon balance. Stoichiometric WC contains 6.13% carbon; we specify total carbon at min. 6.11% with free carbon held to max. 0.03%.
Those two numbers have to be read together. Too little total carbon and the eta phase (a brittle W-Co-C double carbide) forms during sintering, cracking the finished part. Too much, and uncombined graphite is left in the microstructure as porosity that drops transverse rupture strength. The narrow window between them is the specification that separates usable WC from scrap, which is why free carbon is measured rather than assumed.
Grain size is offered in four bands — 2.5, 5.0, 10.0 and 15.0 µm F.S.S.S. — paired with apparent densities of 2.4, 3.2, 4.8 and 6.0 g/cc. In cemented carbide, WC grain size carries directly through to the sintered grade: finer powder gives higher hardness and edge retention, coarser powder gives toughness and thermal shock resistance.
Specifications
| Average particle size (F.S.S.S.) | 2.5 | 5.0 | 10.0 | 15.0 µm |
|---|---|
| Apparent density | 2.4 | 3.2 | 4.8 | 6.0 g/cc |
| Total carbon (bonded), min. | 6.11 % |
| Free carbon, max. | 0.03 % |
| Tungsten (W) | Balance |
| Typical impurities | Fe, Mo, Cu, Na, Co, Ca, Mg, Mn, Zn — max. limits stated per CoA |
| HS code | 2849.90 |
Specifications can be tailored to order. Confirm your target values with us before placing an order and we will state honestly whether they are achievable.
Matching WC grain size to the finished grade
WC grain size survives milling and sintering, so the powder you buy largely determines the hardness-toughness position of the grade you sell. Cobalt content moves that position too, but it cannot rescue a grain size chosen wrongly.
2.5 µm (2.4 g/cc)
Fine-grain cemented carbide for cutting inserts and precision wear parts where hardness and edge retention lead.
5.0 µm (3.2 g/cc)
General-purpose carbide grades — the broadest-use band and the usual qualification starting point.
10.0 µm (4.8 g/cc)
Tougher grades for interrupted cuts, mining tips and impact loading.
15.0 µm (6.0 g/cc)
Coarse grades for rock drilling and heavy wear, and for diamond segment matrices needing bulk abrasion resistance.
Applications
Cemented carbide production
Milled with cobalt or nickel binder, pressed and liquid-phase sintered into inserts, dies, rolls and wear parts. This is the largest single use of WC powder and the one most sensitive to carbon balance, because eta phase forms during the sintering step rather than in the powder itself.
Diamond segment matrices
WC raises the abrasion resistance of the bond so it wears in step with the diamond. Coarser grades are usual because the matrix needs bulk wear resistance rather than sintering activity.
Wear-resistant tooling and dies
Drawing dies, nozzles, punches and seal faces made from WC hold dimension against abrasive flow far longer than hardened steel, making a higher material cost straightforward to justify on tool life.
Thermal spray feedstock
WC-Co and WC-Ni powders for HVOF coatings start from carbide powder. Free carbon matters especially here, since decarburisation during spraying only makes an existing carbon deficit worse.
Quality control
- Total and free carbon determined on every lot
- Fisher sub-sieve sizer (F.S.S.S.) grain size
- Apparent density by Scott volumeter
- Impurity scan against agreed maximum limits
- Certificate of analysis with every shipment, retained samples held against lot number
Manufactured under an ISO 9001:2015 certified quality management system.
Packaging and export
Supplied in sealed drums or lined pails with tamper-evident closure, palletised for container shipment. WC is less oxygen-sensitive than metal powder, so packing is specified for moisture exclusion and handling safety rather than inert atmosphere.
Commercial invoice, packing list, certificate of analysis and certificate of origin are supplied as standard with every export shipment.
Tungsten carbide powder — frequently asked questions
What carbon content do you hold?
Total carbon min. 6.11% bonded, with free carbon max. 0.03%. Stoichiometric WC is 6.13% carbon, so the specification sits deliberately close to it — both figures are reported on the certificate of analysis for every lot.
Why does free carbon matter so much?
Uncombined graphite in the powder ends up as porosity in the sintered part and pulls down transverse rupture strength. A carbon deficit is the opposite failure: it lets brittle eta phase form during sintering. The usable window between those two is narrow, which is why free carbon is measured rather than estimated.
Which grain size should I start with?
5.0 µm F.S.S.S. is the broadest-use grade and the normal starting point for qualifying a new cemented carbide grade. Move to 2.5 µm for hardness and edge retention, or to 10.0 and 15.0 µm for toughness under impact.
Can you supply to a specific grain size and apparent density pairing?
The four standard pairings cover most requirements. Combinations outside them can be discussed for larger orders — send the target and the application and we will confirm what is achievable before you commit to an order.
Do you supply chemistry formatted for REACH or SDS obligations?
Yes. For export orders we provide a full composition table on the certificate of analysis to support incoming-material qualification and, where applicable, REACH safety data sheet obligations.
Tungsten carbide powder export destinations
Country-specific specifications, logistics and compliance notes for this product: