Stellite Grades Compared
The table sets the five grades side by side using the nominal analyses published on Deloro's Stellite material data sheets. All are cobalt balance with 27 to 30% chromium; the other columns are what separate them.
| Grade | Tungsten % | Molybdenum % | Carbon % | Hardness | Typical use |
|---|---|---|---|---|---|
| Stellite 1 | 13.0 | minor | 2.5 | 51 to 60 HRC | Pump sleeves, seal rings, wear pads |
| Stellite 3 | 13.0 | – | 2.5 | 48 to 63 HRC | Same duties, supplied as castings and PM/HIP parts |
| Stellite 6 | 4.5 | minor | 1.2 | 36 to 46 HRC | Valve seats and gates, general wear |
| Stellite 12 | 8.5 | minor | 1.8 | 46 to 51 HRC | Industrial knives, saw tips, valve hardfacing |
| Stellite 21 | – | 5.5 | minor | 27 to 40 HRC | Valve trim, cavitation and galling service |
Stellite 6 and Stellite 21 have their own pages with full composition, identification and FAQs. Stellite 19 also appears on some buying lists; we could not confirm its nominal analysis from a producer data sheet, so it is not tabled here.
What Is Stellite Scrap?
Stellite is a family of cobalt-chromium alloys hardened by carbides. The rule of thumb is simple: more tungsten and more carbon give more carbide, more hardness and better resistance to abrasion, at the cost of toughness. Stellite 1 sits at the hard end, Stellite 6 in the middle as the general-purpose grade, and Stellite 21 at the tough, corrosion-resistant end with molybdenum in place of tungsten.
Most Stellite is never made as plate or bar. It is deposited as hardfacing from rod, wire, electrodes or powder, or cast into small wear parts. A Stellite scrap lot is therefore usually one of three things: consumable surplus (rod stubs, wire ends, powder), small castings and PM parts (seat rings, sleeves, saw tips, knife edges), or steel parts carrying a Stellite overlay. Only the first two are sold as Stellite; overlaid parts are mostly steel.
For a melter or powder maker, the grade matters because tungsten content ranges from 0 to 13%. A heat made for Stellite 6 cannot absorb Stellite 1 returns without overshooting tungsten and carbon, and a Stellite 21 melt does not want tungsten at all. That is why we buy by grade, not as "mixed Stellite".
Stellite is a trademark of its owner; the name is used here only to identify alloys in scrap lots.
How Stellite Scrap Grades Are Identified
| Reading | Points to |
|---|---|
| Tungsten about 13% | Stellite 1 or 3 |
| Tungsten about 8.5% | Stellite 12 |
| Tungsten about 4.5% | Stellite 6 |
| No tungsten, molybdenum about 5.5% | Stellite 21 |
| High iron on any grade | A deposit diluted by its steel base |
Handheld XRF reads tungsten, molybdenum and chromium well enough to sort most lots. Carbon, which separates Stellite 1 from 3 and confirms the hard grades, needs spark OES or a combustion analyser. See XRF, OES or a lab?
Stellite Scrap Forms We Buy and Sell
| Form | Typical source | How it is valued |
|---|---|---|
| Rod, wire and electrode stubs | Hardfacing shops and distributors | As alloy, by grade on the label |
| Powder (sealed, labelled) | PTA, laser cladding and HVOF users | As alloy if single-grade and uncontaminated |
| Castings and PM parts | Seat rings, sleeves, saw tips, knife edges | As alloy after a grade check |
| Grinding swarf | Finishing of hardfaced parts | Below solids; needs drying and grit removal |
| Overlaid steel parts | Valve gates, discs, pump sleeves | Mostly as steel, with a cobalt credit if agreed |
What Sets the Offer for Stellite Scrap
- Cobalt content, which is the main value in every grade.
- Tungsten credit, from nothing in Stellite 21 to about 13% in Stellite 1.
- Alloy fraction: solid alloy against overlays on steel.
- Iron pick-up and contamination with other hardfacing alloys.
- Labels, batch cards and readings that prove the grade.
- Lot size and packing.
No price list is published; offers are dated because cobalt and tungsten move independently.
How to Sell or Buy Stellite Scrap
- Send the grade if known, the form, weight, location and photographs of labels or markings.
- Keep each grade and each form in its own container.
- We review incoming enquiries and respond with relevant next steps.
- Terms and documents are agreed in writing; lots ship under heading 8105.30.
Offer a lot · Place a requirement · All cobalt alloys · Tungsten carbide scrap
Mipra Steel imports and buys Stellite scrap in India and exports it: see Stellite scrap importer and buyer and Stellite scrap exporter from India. Lots are sorted and prepared before dispatch: how we sort and prepare scrap lots. Much of what we buy comes from South India, and our head office is in Khetwadi, Mumbai.
Related: Cobalt alloy grades in Indian scrap.
Stellite scrap FAQ
Which Stellite grade is hardest?
Of the grades listed here, Stellite 1 and Stellite 3, with about 13% tungsten and 2.5% carbon, are the hardest (around 48 to 63 HRC). Stellite 21 is the softest and toughest.
What does HS 6 or HS 21 mean on a scrap list?
Older buying lists abbreviate Haynes Stellite grades as HS followed by the grade number, so HS 6 is Stellite 6 and HS 21 is Stellite 21. HS 25 is Haynes 25 (L-605) and HS 31 is X-40.
Can mixed Stellite grades be sold together?
They can be sold, but at the value of the least useful grade in the lot. A melter making one grade cannot use another without correcting tungsten, carbon or molybdenum, so sorted lots are worth more.
Is hardfaced steel counted as Stellite scrap?
No. A part with a Stellite overlay is mostly steel. It is valued on the overlay it carries, by agreement, not as solid Stellite.
Which HS code applies to Stellite scrap?
Heading 8105.30, cobalt waste and scrap, because cobalt is the largest element. Confirm the national line with your customs broker.
Does Mipra Steel buy Stellite scrap outside Mumbai?
Yes. Mipra Steel buys Stellite scrap from sellers across India, and much of it comes from South India: Bengaluru, Hyderabad, Chennai, Coimbatore and Visakhapatnam.
Sources and Review
Figures are quoted as published in these sources; any value we could not confirm has been left out.
- Deloro material data sheets (rev. 00) for Stellite 1, Stellite 3, Stellite 6, Stellite 12 and Stellite 21: nominal compositions, hardness, density, applications and product forms.
Reviewed by Mitesh Shah, Proprietor, Mipra Steel · Published by Mipra Steel, Khetwadi, Mumbai · Last updated