Cobalt-Chrome Alloy Stellite 3
Stellite 3 is a high-carbon, high-tungsten cobalt-chromium hardfacing alloy strengthened by a dense network of primary carbides.
Reference datasheet — Stellite 3 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the AS-CAST condition
Stellite 3 tempers and conditions
Stellite 3 is supplied in 2 conditions, soft to hard. AS-CAST is the default FabDigit quotes; the values on this page are for it.
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As-Welded | Pick for manual hardfacing of wear pads and edges where some substrate dilution is acceptable. | 540 | 550 | 0 | 53 HRC | 1.8 % IACS |
AS-CASTDefault cast rod / cast component, no post heat treatment | Standard stocked form: chill-cast welding rod and investment/sand-cast wear parts used as-cast. | 600 | 620 | 0.5 | 55 HRC | 1.8 % IACS |
Supply forms, finishes and certifications
Ways Stellite 3 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
HVOF | HVOF / plasma-sprayed coating from powder | Coating |
PTA | PTA / laser-clad deposit from powder | Coating |
What is Stellite 3?
Stellite 3 is a high-carbon, high-tungsten cobalt-chromium hardfacing alloy strengthened by a dense network of primary carbides. It offers the highest as-cast hardness of the common Stellite series — about 55 HRC with 620 MPa tensile strength and 0.5 % elongation — and is supplied as cast rod, castings, GTAW and PTA deposits and HVOF powder. It is brittle and grind-only, rated to 800 °C, and check cracking in overlays is normal for abrasion service. Stellite 6 (ERCoCr-B) is the tougher alternative where impact is present. Stellite 3 has a density of 8.6 g/cm³ (0.311 lb/in³), heavier than 63% of cobalt-chrome alloy grades. It melts at 1,240°C (2,264 °F). Stellite 3 has a yield strength of 600 MPa (87 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 52% of cobalt-chrome alloy grades. Elongation at break is 0.5% and the elastic modulus is 230 GPa (33.4 Msi).
What is Stellite 3 used for?
- valve seats
- cutting tool tips
- extrusion dies
- extreme abrasion surfaces
Advantages
- Low embodied carbon — 10.5 kg CO₂/kg, better than 77% of cobalt-chrome alloy grades
Limitations
- Low fracture toughness — 11 MPa·√m (10 ksi·√in), worse than 97% of cobalt-chrome alloy grades
- Limited ductility — 0.5%, worse than 89% of cobalt-chrome alloy grades
- Needs corrosion protection — 60/100, worse than 89% of cobalt-chrome alloy grades
- Difficult to weld — 20/100, worse than 87% of cobalt-chrome alloy grades
Stellite 3 properties
Typical room-temperature values for Stellite 3-AS-CAST; bars are the position among cobalt-chrome alloy grades.
Physical3
Stellite 3 has a density of 8.6 g/cm³ (0.311 lb/in³), heavier than 63% of cobalt-chrome alloy grades. It melts at 1,240°C (2,264 °F).
Mechanical15
Stellite 3 has a yield strength of 600 MPa (87 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 52% of cobalt-chrome alloy grades. Elongation at break is 0.5% and the elastic modulus is 230 GPa (33.4 Msi).
Thermal5
Stellite 3 is rated for continuous service to 800°C (1,472 °F). It conducts heat at 14.5 W/m·K (8.38 BTU/hr·ft·°F), better than 64% of cobalt-chrome alloy grades. Thermal expansion is 10.8 µm/m·K (6 µin/in·°F).
Electrical3
Stellite 3 conducts electricity at 1.8 % IACS, worse than 75% of cobalt-chrome alloy grades.
Chemical & Environmental3
Corrosion resistance is good (60/100), worse than 89% of cobalt-chrome alloy grades.
Sustainability4
Producing a kilogram of Stellite 3 takes about 135 MJ of energy and emits 10.5 kg of CO₂ — less than 82% of cobalt-chrome alloy grades. Typical recycled content is 20%.
Manufacturability8
Stellite 3's machinability is not recommended (4/100, worse than 95% of cobalt-chrome alloy grades); weldability poor (20/100); formability not recommended (2/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the cobalt-chrome alloy family
Yield strength against density for every cobalt-chrome alloy grade FabDigit runs. Stellite 3 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Stellite 3
Is Stellite 3 easy to machine?
Treat as grind-only: use CBN or SiC/diamond wheels; carbide turning is impractical above ~50 HRC and the carbide network destroys edges rapidly.
Can Stellite 3 be welded?
Deposit by oxyacetylene, GTAW or PTA with 300–650 °C preheat, slow interpass cooling and slow post-weld cool; relief check-cracking in the deposit is normal and generally acceptable for abrasion service.
Can Stellite 3 be formed, bent or molded?
No cold or hot forming — supplied as cast rod, castings or atomised powder; shape by casting or near-net cladding.
Stellite 3 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Chigh carbon — forms primary Cr/W carbides | 2 – 2.7 | 2.4 |
| Cr | 29 – 32 | 30.5 |
| W | 11 – 13.5 | 12.5 |
| Ni | ≤ 3 | 1.5 |
| Fe | ≤ 3 | 1.5 |
| Si | ≤ 1 | 0.6 |
| Mn | ≤ 1 | 0.5 |
| Mo | ≤ 1 | 0.3 |
| Cobalance, nominally ~48–52 % | balance |
What surface finishes work on Stellite 3?
Finish by grinding, lapping or polishing to a fine wear surface; no anodising, and plating/painting are unnecessary since the alloy is inherently passive.
How much does Stellite 3 cost?
Stellite 3 is a high-cost cobalt-chrome alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Stellite 3 — frequently asked
What is Stellite 3 used for?
Stellite 3 is typically used for valve seats, cutting tool tips, extrusion dies and extreme abrasion surfaces. In short: hardest common Stellite; carbide-rich abrasion grade; cast or overlay only.
What is the yield strength of Stellite 3?
Stellite 3 has a typical yield strength of 600 MPa (87 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 52% of cobalt-chrome alloy grades. Strength varies by condition: see the 2 listed tempers.
Is Stellite 3 easy to machine?
Not especially — machinability is rated not recommended (4/100, worse than 95% of cobalt-chrome alloy grades). Treat as grind-only: use CBN or SiC/diamond wheels; carbide turning is impractical above ~50 HRC and the carbide network destroys edges rapidly.
Can Stellite 3 be welded?
Not readily — weldability is rated poor (20/100). Deposit by oxyacetylene, GTAW or PTA with 300–650 °C preheat, slow interpass cooling and slow post-weld cool; relief check-cracking in the deposit is normal and generally acceptable for abrasion service.
What surface finishes work on Stellite 3?
Finish by grinding, lapping or polishing to a fine wear surface; no anodising, and plating/painting are unnecessary since the alloy is inherently passive.
Can Stellite 3 be formed, bent or molded?
No cold or hot forming — supplied as cast rod, castings or atomised powder; shape by casting or near-net cladding.
What is the maximum service temperature of Stellite 3?
Stellite 3 is rated for continuous use to about 800°C (1,472 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Stellite 3 AS-CAST and Stellite 3 AW-GTAW?
AS-CAST is the default condition — standard stocked form: chill-cast welding rod and investment/sand-cast wear parts used as-cast. AW-GTAW: pick for manual hardfacing of wear pads and edges where some substrate dilution is acceptable. Yield strength is 600 MPa in AS-CAST versus 540 MPa in AW-GTAW.
How much does Stellite 3 cost?
Stellite 3 is a high-cost cobalt-chrome alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- Stellite 3 alloy datasheet (cast rod and powder) — Kennametal Stellite / Deloro Wear Solutions (2022)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys (Cobalt-base wear alloys) — ASM International (1990)
- ASM Handbook Vol. 13B — Corrosion: Materials (Cobalt alloys) — ASM International (2005)
- AWS A5.21 — Bare Electrodes and Rods for Surfacing (Co-Cr-W classes) — AWS (2011)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.