Key takeaways
- Turbine blade scrap is cast nickel superalloy and is sold by exact alloy, not as generic nickel scrap.
- Part numbers and engine or turbine model narrow the alloy; XRF confirms heavy elements, while aluminium, hafnium and rhenium need OES or a lab.
- Keep rhenium-bearing, coated, repaired, cobalt-base and foundry material in separate lots.
- Remove seal pins, dampers, shims and other hardware, which are often a different alloy.
- Value follows proof of alloy, because only proven blades can return to their own alloy.
Turbine blade scrap looks more uniform than it is. A crate of first-stage buckets from a gas turbine outage, a box of cut-up high-pressure blades from an engine shop and a drum of small vanes from a turbocharger rebuild are all grey, curved, non-magnetic castings. Underneath, they can be half a dozen different superalloys with very different amounts of cobalt, tungsten, tantalum, hafnium and rhenium, and a melter pays for that chemistry only when it is sure of it.
This article is about the parts themselves: what counts as turbine blade scrap, which alloys sit in which parts, how to narrow down an unknown box, and how coatings, repairs and loose hardware change a lot. For what happens to the metal once a melter has it, see how superalloy revert returns to the melt.
What Counts as Turbine Blade Scrap?
Turbine blade scrap means the cast superalloy parts from the hot section of a gas turbine: rotating blades, called buckets in industrial machines, and stationary vanes, called nozzles. Vane segments, shroud pieces and integrally cast wheels from small turbines are usually sold alongside them.
Three sources supply most of it. Aero engines retire high- and low-pressure turbine blades and vanes at shop visits; these are small, precise parts, often directionally solidified or single-crystal, and they are normally mutilated before release so they cannot return to service. Power generation turbines replace much larger buckets and nozzle segments at hot-gas-path inspections and major overhauls. Turbocharger and small-turbine wheels, frequently Inconel 713C, make up a smaller third stream.
Compressor and fan blades are not turbine blade scrap. They sit at the cold end of the engine and are mostly titanium alloy, such as Grade 5 titanium, or steel. Keep them out of a superalloy lot completely.
How Does Aero Blade Scrap Differ from IGT Blade Scrap?
Aero and IGT blade scrap are the same kind of material, cast nickel superalloy, but they arrive in very different shapes and with different paperwork. Knowing which you hold tells a buyer what questions to ask.
- Size and count. Aero blades are small and numerous, so lots are usually weighed by container and counted by part number. IGT buckets and nozzle segments are large and heavy, and a single outage can fill several crates with one part type.
- Casting structure. Aero high-pressure blades are often directionally solidified or single-crystal. IGT buckets are cast equiaxed or directionally solidified depending on the stage and design.
- Condition. Aero parts are normally cut or crushed before release. IGT parts usually arrive whole, sometimes after one or more repair cycles.
- Paperwork. Aero material comes with scrapping or release records from the engine shop. IGT material is traced by turbine model, stage and outage records from the plant or repair shop.
Neither stream is better than the other. What matters is that each container holds one alloy from one source, with the records to prove it.
Which Superalloys Are Turbine Blades Made from?
Turbine blades and vanes are cast from γ′-strengthened nickel superalloys, and the alloy depends on the part, the stage and the age of the engine design. The table shows the usual pairings.
| Part | Typical alloys | What to watch |
|---|---|---|
| Aero high-pressure turbine blades | René N5, René 125, René 108, MAR-M 247 | Single-crystal parts may carry rhenium; hafnium in DS alloys |
| Older aero and low-pressure blades | René 80, René 77, Udimet 500, MAR-M 246 | Similar-looking alloys with different cobalt and tungsten |
| IGT first- and second-stage buckets | GTD-111, René 80 | Tantalum separates the two |
| IGT nozzles and vanes | GTD-222, GTD-241, GTD-262, IN-939 | One shared base; small differences decide the alloy |
| Small turbine and turbocharger wheels | Inconel 713C, MAR-M 246, MAR-M 247 | 713C has no cobalt |
René 80 and GTD-111 are the classic look-alike pair in bucket scrap. Both are about 14% chromium, 9.5% cobalt and 5% titanium. GTD-111 carries about 2.8% tantalum and René 80 none, while René 80 has more molybdenum. A lot sold as René 80 that reads tantalum is a different alloy, and a melter making René 80 cannot use it as such.
The nozzle alloys are closer still. GTD alloys 222, 241 and 262 share a base of about 22.5% chromium and 19% cobalt; tantalum separates 222 from 241, and about half a per cent of aluminium separates 241 from 262. IN-939 sits on a similar base with more titanium. Part numbers and casting documents matter more here than anywhere else in blade scrap.
How Do You Identify the Alloy in a Box of Blades?
Start with the part and its paperwork, then confirm with analysis. A part number with the engine or turbine model narrows the alloy faster than any analyser, and the reading then checks that the box holds what the label says.
Handheld XRF reads the heavy elements well: nickel, cobalt, chromium, tungsten, tantalum, molybdenum and niobium. Aluminium, hafnium and rhenium are the problem. Aluminium needs a light-element setup or spark OES, and rhenium's X-ray lines overlap with tantalum and tungsten, so it is normally confirmed in a laboratory. XRF, OES or lab analysis explains which method answers which question. The gates below are a first sort, not a final identification.
- Is cobalt the main element, not nickel?Yesa cobalt-base vane lot, kept apart from all nickel superalloy
- About 22.5% chromium and 19% cobalt?YesGTD-222, 241 or 262, or IN-939, confirmed by OES or lab
- About 14% chromium and 5% titanium?YesRené 80 or GTD-111, tantalum decides
- About 10% tungsten and 10% cobalt?YesMAR-M 246, MAR-M 247 or René 108, hafnium separates 246 and part numbers settle the rest
- High tantalum with chromium near 7%?Yespossible rhenium-bearing single crystal such as René N5, lab check for rhenium
- No cobalt, about 4% molybdenum and 2% niobium?YesInconel 713C wheels or blades
- Hold the lot and send a sample for laboratory analysis
Single-Crystal, Directionally Solidified or Equiaxed
Casting structure does not change the alloy's name, but it tells you about its generation. After a light macro-etch, an equiaxed casting shows randomly oriented grains, a directionally solidified blade shows long grains running along its length, and a single-crystal blade shows no grain boundaries at all. Single-crystal high-pressure blades are where rhenium appears, so treat any single-crystal lot as possibly rhenium-bearing until an analysis says otherwise. γ′ and why superalloys stay strong when hot explains the rhenium generations.
How Do Coatings Affect Turbine Blade Scrap?
Coatings change the chemistry a melter receives, so coated and uncoated blades are sold as separate lots and every coating should be declared. Most service blades and vanes carry at least one coating layer, and hot first-stage parts often carry several.
- Ceramic topcoatthermal barrier coating, usually yttria-stabilised zirconia, on the hottest parts
- Thermally grown oxidea thin alumina layer that forms in service
- Bond coatMCrAlY overlay, or a plain or platinum aluminide diffusion coating
- Superalloy base metalthe cast alloy the melter is actually paying for
Each layer brings something the base alloy does not want in excess: aluminium, chromium and yttrium from overlays, platinum from platinum aluminides, and zirconia ceramic from thermal barriers. Melters either strip coatings before remelting or limit how much coated material goes into a charge. Either way they need to know. Describe each lot as uncoated, aluminide, platinum aluminide, overlay or thermal barrier coated, and photograph the coated surfaces.
Foundry revert, such as gates, risers and rejected castings that never entered service, is uncoated and has a known chemistry. Keep it apart from service blades; mixing the two throws away the advantage of the cleaner material. The castings and revert page covers foundry material.
Repaired, Brazed and Service-Damaged Blades
Repaired blades are sellable, but they belong in their own lot because a repair adds metal that is not the base alloy. Weld-repaired tips and edges are often built up with a different filler. Braze repairs use nickel-base fillers that typically contain boron and silicon to lower their melting point, and melters limit both elements tightly.
Service damage matters less than people expect. Burnt tips, erosion and impact damage reduce weight but do not change the alloy. Deposits are a different matter: combustion residues can carry sulfur, which harms superalloy strength and oxidation resistance at very low levels, and cooling passages can hold dirt or, in foundry rejects, ceramic core residue. Knock out loose material and declare heavy deposits. Tramp elements in remelting explains why trace contamination weighs so heavily.
How Do You Prepare a Turbine Blade Lot for Sale?
Prepare a blade lot so that every container holds one alloy from one engine or turbine type, with nothing in it that isn't that alloy. The checklist covers what buyers look for first.
- One alloy, one engine type per containernever top up a box with blades from another machine
- Rhenium-bearing parts sealed apartsingle-crystal high-pressure blades in their own labelled container
- Coated, uncoated and repaired sortedeach declared on the packing list
- Hardware removedseal pins, dampers, lock plates, shims and bolts taken out
- Foundry revert kept separategates, risers and rejects never mixed with service parts
- Count, weight and photographsper container, with close-ups of part numbers
- Paperwork kept with the lotengine or turbine model, part numbers, scrapping or release notes
Loose hardware deserves a second look. Seal pins, dampers, shims and lock plates are often a different alloy from the blade, and a few of them in a box of buckets are enough to fail a lot on analysis. Cut-up aero blades should stay in the containers they were released in, so the paperwork still matches the contents.
Send the grade, form, approximate quantity and location.
What Drives the Value of Turbine Blade Scrap?
Turbine blade scrap is valued on its contained alloying elements and on how certain the buyer can be of them. Cobalt, tungsten, tantalum, hafnium and rhenium are what make blade alloys worth more than ordinary nickel scrap, and they are paid for in full only when the alloy is proven and the lot can go back into that alloy.
The chart shows why blind mixing costs money: tantalum ranges from about 6.5% in René N5 to none in René 80. A mixed box averages those differences into a chemistry no foundry alloy matches. Other factors that move an offer:
- Alloy certainty: part numbers, engine model and readings that agree with each other.
- Rhenium segregation: rhenium-bearing parts kept apart, and proved by a laboratory.
- Coating and repair status: uncoated, unrepaired material is the easiest to remelt.
- Cleanliness: no hardware, deposits or foreign alloys.
- Lot size: a melter can plan around a consistent quantity of one alloy.
The contained metal calculator works out the cobalt and tungsten in a lot by alloy, and what decides the value of a lot covers the general principles.
Paperwork and Shipping for Blade Scrap
Blade scrap moves more easily when the paperwork proves both the alloy and the part's retirement. For aero parts, keep the scrapping or release record and note that parts were mutilated; mutilation does not affect melt value. For IGT parts, record the turbine model, stage and outage. The aerospace scrap page covers engine-shop material more broadly.
For export, nickel-base superalloy scrap is normally classified under HS heading 7503, nickel waste and scrap. Cobalt-base vanes are a different metal and do not belong under the nickel heading, which is another reason to keep them apart. Documents to prepare before exporting alloy scrap lists the rest, including radiation certificates. When your lot is sorted, send the alloy, count, weight and photographs and we'll review your enquiry. The René alloy scrap pages give compositions for each blade alloy.
Submit a requirement with the grade, form, quantity and delivery location.
Source a GradeFAQ
Are turbine blades valuable as scrap?
Yes. Blades and vanes are cast from nickel superalloys containing cobalt, tungsten, tantalum, hafnium and sometimes rhenium, so sorted blade scrap is worth well above ordinary nickel scrap. That value depends on proof of alloy. A mixed, unidentified box is worth far less than the same weight sorted by alloy with part numbers and readings, because only sorted material can return to its own alloy.
What is the difference between a bucket and a blade?
Nothing metallurgical. Bucket is the term used for rotating turbine blades in industrial gas turbines, while blade is the usual aero engine term. In the same way, nozzle is the industrial term for a stationary vane. For scrap purposes, what matters is the alloy, the stage and whether the part is coated or repaired, not the name.
Can blades from different engines be mixed in one lot?
Not if you want full value. Different engine and turbine models use different alloys, and even one model may use different alloys in different stages. Mixing them produces a chemistry that matches no foundry alloy, so the lot has to be analysed and usually sold into a lower-value route. Keep each engine type, stage and alloy in its own container.
Are some turbine vanes cobalt-base rather than nickel-base?
Yes. Some vanes and nozzle segments are cast from cobalt-base superalloys rather than nickel-base ones. On an analyser they read cobalt as the main element. They go to a different melt, belong under a different tariff heading and must never be mixed with nickel-base blades. Check every vane lot for its base element before it is described.
Why do buyers ask for photographs of turbine blades?
Photographs show the part type, stage, size, coating colour, repairs, damage and any legible part numbers, which together narrow the alloy before anyone tests it. They also let a buyer spot loose hardware, mixed parts or heavy deposits. Take an overview of each container and close-ups of markings, coated surfaces and any repaired areas.
Do single-crystal blades always contain rhenium?
No. First-generation single-crystal alloys carry no rhenium, while second-generation alloys such as René N5 carry about 3% and third-generation alloys more. Because the blades look alike and handheld XRF cannot measure rhenium reliably, treat single-crystal blades as possibly rhenium-bearing and keep them apart until a laboratory analysis settles it.
Can damaged or burnt turbine blades still be sold?
Yes. Burnt tips, erosion, cracks and impact damage reduce the weight of metal but do not change the alloy, so damaged blades are sold by alloy like any other. Remove loose debris and hardware, and declare heavy deposits or repairs, which matter more to a melter than the damage itself.
