Tungsten Carbide Scrap: Grades, Specifications, Testing & International Supply

Tungsten carbide is a chemical compound of tungsten and carbon, written WC. In its pure compound form it is a hard, brittle powder — it is not usable as a tool material on its own. To make an industrial component, WC powder is milled with a metallic binder, pressed to shape and sintered at high temperature so the binder melts and cements the carbide grains into a dense solid. The result is a composite properly called cemented carbide, and in most of Europe and Asia it is simply called hardmetal (or hard metal). The most common binder is cobalt, which is why the material family is usually written WC-Co.

In everyday trading language "tungsten carbide scrap", "hardmetal scrap" and "cemented carbide scrap" are used interchangeably to mean end-of-life or off-specification WC-Co components. A supplier who says "carbide inserts" and a processor who says "WC-Co hard scrap" are usually describing the same physical material. Understanding that these terms overlap prevents a common procurement error: assuming a differently-worded offer is a different material.

The binder content is the single most important structural variable. Grades with a low binder fraction are harder and more wear resistant and are typical of cutting tools; grades with a higher binder fraction are tougher and more impact resistant and are typical of mining bits, rock tools, stamping dies and wear parts. Some grades also contain additional carbides — titanium carbide, tantalum carbide, niobium carbide — added to control edge wear and hot hardness, and some use nickel rather than cobalt as the binder, particularly where corrosion resistance matters. All of these variations survive into the scrap stream and all of them affect how a processor values a lot.

Tungsten metal and tungsten carbide are not the same material and should never be offered as one lot. Tungsten metal scrap — electrodes, wire, sheet, crucible parts, heavy alloy counterweights — is elemental tungsten or a tungsten-rich alloy with no carbon compound structure. Tungsten carbide scrap is the WC-Co composite described above. They look superficially similar because both are grey and unusually heavy, but they follow different recovery routes and are valued on different bases. A practical field distinction: tungsten metal parts are typically machined or drawn forms and can be ductile in thin sections, while cemented carbide is sintered, extremely hard and brittle — it chips rather than bends. Confirmation still requires analysis.

Industrial applications that generate carbide arisings are broad: metal cutting (turning, milling, drilling, threading, reaming), wear protection (nozzles, seals, bushings, guides), forming (drawing dies, punches, cold heading tooling), mining and construction (rock drill bits, roadheader picks, tunnelling tools), oil and gas (drill bit inserts, downhole wear components), and woodworking and recycling machinery (saw tips, shredder knives).

The table below maps the tungsten-bearing streams Nautica handles commercially. Each stream links to its dedicated product page, where the sourcing, sorting and packing notes for that material are set out. No chemistry or recovery percentage is stated in advance for any stream — those are established for the actual lot, by inspection and by whatever analysis is agreed contractually.

Read the table as a description of what a buyer is likely to receive and what they should check, rather than as a specification. The most useful column for procurement is contamination: it is contamination, far more than nominal grade, that separates a straightforward lot from a difficult one.

Carbide recyclers divide the entire scrap universe into two families, and almost every commercial disagreement about a carbide lot traces back to which family it really belongs to.

Hard scrap is fully sintered, solid cemented carbide: inserts, end mills, drills, rods, dies, wear parts, mining and drilling components, and the carbide portion of brazed tooling. It is dense, hard and physically stable. Its tungsten is locked in a solid body that can be handled, weighed, visually sorted and surface-tested with reasonable confidence. Hard scrap is the stream that suits the zinc-reclaim recovery route, which recovers the material without fully breaking down its chemistry — one reason clean single-grade hard scrap is the most straightforward carbide material to trade.

Soft scrap covers everything that is not a solid sintered body: unsintered or partially sintered pressed compacts, green scrap from pressing operations, loose WC and WC-Co powders, spray powders, and grinding residues. Its tungsten content is real, but it is dispersed, variable and mixed with process materials. Soft scrap is normally routed to chemical or oxidation-based recovery rather than zinc reclaim, and it is priced on analysis rather than on appearance.

Grinding sludge and swarf sit at the difficult end of soft scrap. Tool regrinding produces fine carbide particles suspended in coolant, oil and abrasive wheel debris, often with steel fines from the shank. The tungsten is genuinely recoverable and this material is routinely recycled, but the lot arrives wet, heterogeneous and heavy with non-carbide mass. Moisture and free liquid affect both weight and transport handling, so declared weight, drying state and packing method matter more here than in any other carbide stream.

Mixed carbide is hard scrap with an unknown or blended grade composition — several tool families in one drum, coated and uncoated pieces together, or unavoidable inclusions of high speed steel and other tool materials. It is recyclable and widely traded, but because the processor cannot assume a single grade, it is normally handled on an analysed or discounted basis rather than as clean single-grade material.

Brazed carbide is a hybrid case: a carbide tip joined to a steel body with a silver-bearing or copper-bearing braze alloy. The carbide is genuine hard scrap, but only part of the piece's weight is carbide, and the braze and the steel body must be separated during processing. Buyers therefore evaluate brazed tools on estimated carbide content, not gross weight — which is why brazed lots and de-tipped lots should never be quoted as if they were the same material.

Evaluation of a carbide lot is an attempt to answer one question: how much recoverable tungsten-bearing material is actually present, and how much work stands between the delivered lot and that recovered material. Every criterion below feeds that judgement.

Tungsten content is the primary driver. In cemented carbide the tungsten is present as WC, so what the processor is estimating is the carbide fraction of the delivered mass, net of binder, additional carbides, attachments and contamination. Cobalt binder content matters twice over: it changes the grade's behaviour in recovery, and cobalt itself carries independent value that is commonly recognised in the commercial evaluation of higher-binder material.

Grade consistency determines how much sorting cost the processor has to absorb. A drum of one insert type from one machine shop is easier to value than a drum blending turning inserts, mining picks and die scrap, even when the total tungsten is comparable. Coatings — titanium nitride, aluminium oxide, titanium carbonitride and similar layers — are thin relative to the body and are routine in the trade, but they do interfere with surface analysis, which is a testing consideration rather than a value objection.

Foreign metals are the most common cause of a lot being downgraded. High speed steel and tool steel pieces mixed in with carbide look similar to an untrained eye and are far less valuable. Steel attachments — shanks, holders, bodies, retaining screws, clamps — add weight without adding carbide. Brazing material introduces silver or copper into the recovery stream. Ceramic and cermet inserts occasionally appear in tool-room arisings and are not tungsten-bearing at all.

Process residues affect both handling and net weight: cutting oil and coolant on machined arisings, water in sludge and swarf, abrasive grit from grinding wheels, plastic packaging and cardboard from tool boxes, and general workshop debris. Moisture is a particular concern for fine material, both because it inflates weight and because wet fines can compact and shift.

Particle size and physical form govern which recovery route is available. Solid pieces, chips, fines and sludge are processed differently, and a lot that mixes coarse solids with fine residues can require separation before anything else can happen. Mixed-grade lots and lots of unknown provenance are typically approached conservatively until analysis is available.

Nautica does not publish acceptance tolerances or maximum contamination limits in advance. Each lot is offered subject to inspection, sorting, grade and available analysis, and any acceptance criteria — including how contamination is measured and what happens if the lot deviates — are agreed in the sales contract before shipment. Buyers with strict downstream limits should state those limits at enquiry stage so they can be written into the contract rather than discovered on arrival.

X-ray fluorescence (XRF) is the standard first-line analytical tool in commercial carbide trading because it is fast, non-destructive and portable. A handheld analyser excites the surface of a sample and reads the characteristic fluorescent emission of the elements present, returning an elemental profile in seconds. In a carbide context, the elements of practical interest are tungsten, cobalt, nickel, iron, titanium, tantalum, niobium, chromium and vanadium — enough to distinguish cemented carbide from high speed steel, to flag a nickel-binder grade, and to detect obvious foreign metal in a lot.

The value of an XRF reading depends entirely on sampling. A single reading characterises one small area of one piece. To say something meaningful about a drum, a technician takes multiple readings across multiple pieces drawn from different parts of the lot, and treats consistency between those readings as the real result. Where a lot is large or heterogeneous, representative sampling protocols matter more than instrument specification: an excellent analyser used on an unrepresentative sample produces a confident wrong answer.

The most important limitation to understand is that handheld XRF is a surface technique. It reads a shallow layer, which means coatings, braze residue, oxidation, oil films and adhering swarf all influence the reading. A coated insert can under-report tungsten simply because the analyser is partly reading the coating. Carbon — a defining constituent of tungsten carbide — is not measurable by conventional XRF at all, so XRF cannot on its own confirm that a piece is carbide rather than a tungsten-bearing alloy; it infers this from the elemental profile and the physical character of the piece.

XRF is also poorly suited to fine, wet or loose material. Powders, sludge and swarf are not homogeneous at the scale the instrument reads, and free liquid distorts results. These streams are better characterised by laboratory analysis of a dried, homogenised, properly drawn sample, which is why soft scrap tends to be traded on analysis rather than on a field reading.

For mixed lots, XRF is best used as a sorting and screening tool rather than as a valuation instrument: it reliably separates carbide from steel and flags outliers, while the commercial figure is settled by an agreed analysis method. Where third-party verification is required, inspection scope, sampling protocol, testing method, laboratory and acceptance criteria should all be named in the contract rather than assumed. Our approach to third-party inspection is set out on the inspection services page; testing arrangements are agreed per contract and are not applied automatically to every lot.

Tungsten carbide scrap is not an exchange-traded commodity. There is no London Metal Exchange contract for tungsten or for cemented carbide, so it cannot be quoted the way copper or aluminium scrap is quoted — as a published exchange settlement minus a grade discount. Any offer that presents carbide as "LME-linked" is describing something that does not exist.

Instead, the tungsten market references tungsten-specific benchmarks. The most widely cited reference in international trade is the published price of ammonium paratungstate (APT), the intermediate chemical through which most tungsten moves in the supply chain, quoted by specialist metals price reporting agencies. Ferro-tungsten and tungsten concentrate quotations are also used, and cobalt has its own separate market reference. Carbide scrap offers are typically negotiated as a percentage-of-benchmark or as a converted per-kilogram figure derived from those references, rather than from any exchange settlement.

On top of the benchmark, the commercial figure for a specific lot is built from the factors below. In practice these are not applied as a formula but negotiated together, because they interact — a lot with excellent composition but heavy contamination may be worth less than a plainer lot that arrives clean and sorted.

Nautica does not publish list prices for tungsten-bearing material and does not quote against live market figures on this page. Quotations are issued per enquiry, against the described lot, on stated Incoterms and to a stated destination, and remain subject to inspection, sorting, grade and available analysis.

Carbide recycling exists because recovering tungsten from scrap is markedly less energy-intensive than producing it from ore, and because tungsten is classified as a critical raw material in the European Union and several other jurisdictions. Recycled carbide is a material input to the same hardmetal industry that generated it, which makes the loop unusually direct compared with most metal recycling.

Collection is the first stage and largely determines everything downstream. Carbide arisings are segregated at source — a machine shop keeps used inserts in a dedicated bin, a regrinding operation collects its sludge separately, a mining contractor returns worn picks in drums. Material that is segregated at source arrives sortable; material that is swept up together arrives as mixed scrap and is valued accordingly.

Sorting separates hard from soft scrap, removes obvious foreign metal, isolates brazed pieces that require tip recovery, and where the volume justifies it groups material by tool family or apparent grade. Sorting is manual, magnetic and instrument-assisted, with XRF used for screening as described above.

Analysis establishes what the sorted material actually contains. For hard scrap this is often screening plus an agreed sampling protocol; for powders and sludge it is laboratory analysis of a dried and homogenised sample.

Pre-processing prepares the material physically: removing steel shanks and holders, de-tipping brazed tools, degreasing oily arisings, and drying and filtering sludge to remove coolant and free water. Fine and wet streams usually require the most pre-processing effort, which is exactly why they trade at a wider discount than clean solids.

Recovery itself follows one of two broad industrial approaches. The zinc-reclaim process treats sintered hard scrap so that the cobalt binder structure is disrupted and the material can be reduced back to a reusable powder while largely retaining its original carbide grains — it is efficient, but it depends on relatively clean, known-grade hard scrap. Chemical and oxidation-based routes break the material down further, dissolving or converting it so that tungsten and cobalt can be separated and purified; these routes tolerate mixed, contaminated and soft scrap that zinc reclaim cannot handle. Which route a processor uses is the main reason two buyers value the same lot differently. This guide deliberately does not set out process chemistry, reagents or operating conditions — those are hazardous industrial operations for licensed processors, not procurement information.

The output re-enters the supply chain as tungsten-bearing feedstock: reclaimed WC-Co powder returned to hardmetal pressing, or purified tungsten intermediates such as APT that feed powder production, ferro-tungsten and downstream tungsten chemistry. Cobalt recovered alongside it feeds its own downstream markets.

Tungsten carbide is roughly twice as dense as steel, and packing decisions that work for ordinary scrap fail on it. A container's weight limit is reached long before its volume is used, and a badly distributed carbide load concentrates mass into a small footprint — a genuine safety and handling problem rather than a presentational one.

Steel drums are the standard primary packing for solid carbide: inserts, drills, end mills, small dies and wear parts. Drums are filled to a manageable weight rather than to the brim, closed with lever-lock or bolted rings, and labelled individually. Heavy-duty bags are used selectively and only where the material and the handling chain suit them; fine, dense material in an unsupported bag is difficult to lift safely and is generally avoided in favour of drums, reinforced pails or steel-framed boxes. Longer items such as rods and larger mining components are commonly crated or boxed rather than drummed.

Palletisation ties the packing together: drums are placed on pallets, strapped, and where necessary banded to a steel frame so that they cannot shift or topple in transit. Weight distribution across the container floor is planned before loading rather than corrected afterwards — dense units are spread across the floor area instead of stacked in one bay, and stacking heights are kept conservative because of the mass involved.

Moisture protection matters more for carbide than its corrosion resistance suggests, because the concern is the accompanying material: steel shanks rust, oily arisings emulsify, and sludge gains weight and mobility if it takes on water. Liners, sealed closures and dry storage before stuffing are used accordingly, and sludge or wet material is packed in closed containers suitable for the free liquid present.

Lot separation is a commercial requirement as much as a physical one. Where a shipment covers more than one material stream or more than one agreed lot, each is packed, labelled and documented separately so the buyer can verify what arrived against what was contracted. Labelling identifies the material description, lot reference and weight, matched to the packing list.

Package weights are not fixed in advance on this page. Packing configuration is set per lot and per destination, taking account of the material's density, the destination's handling equipment and the agreed Incoterm, and is confirmed in the shipping documentation. The mechanics of how a shipment moves from enquiry to loaded container are set out step by step in our export process hub, and the loading, terminal and sailing arrangements that apply to our cargo are described on the Rotterdam port operations page.

International carbide shipments move on the same commercial documentation as other metal cargo, with a few points where high-value dense material attracts extra attention. What is issued for a given shipment depends on the contract, the destination and the payment method — this list describes what is commonly requested, not a fixed package attached to every order.

The commercial invoice states the parties, the material description, quantity, unit basis, Incoterm and value, and is the reference document for customs valuation. The packing list details the packing units, their individual and total weights and the lot references, and should reconcile exactly with what is physically loaded. The bill of lading is the transport document issued by the carrier and is the instrument the consignee needs to take delivery; its details must agree with the invoice and packing list, particularly on weights and descriptions.

A certificate of origin is issued where the destination or the buyer's customs regime requires it, and is prepared through the competent issuing authority rather than self-declared. Inspection and analysis documentation is provided where it has been agreed in the contract — scope, sampling protocol, method, laboratory and acceptance criteria are defined there, and third-party inspection by an independent agency is arranged at the buyer's request and cost unless agreed otherwise.

A written material specification is prepared for the lot, describing what is being sold in the same terms used in the contract. Loading photographs and documentation of the sealed container are commonly supplied for high-value cargo so the buyer has a record of the condition and configuration at the point of loading.

Buyers should raise documentary requirements at enquiry stage. Letter-of-credit terms, destination customs rules and internal compliance requirements can all impose documents that are straightforward to arrange in advance and disruptive to add after loading.

Carbide offers are difficult to compare because the headline figure — a price per kilogram — hides most of the variables that decide what the material is worth to you. The checklist below is what an experienced buyer establishes before treating two offers as comparable. Sending these points with your enquiry also produces a faster and more accurate quotation, because the seller does not have to price around unknowns.