Cobalt-Chrome Alloy Stellite 3 vs Stellite 6
Cobalt-Chrome Alloy · grade comparison
Cobalt-Chrome Alloy Stellite 3 and Stellite 6 are both cobalt-chrome alloy grades. Stellite 3 is the stronger of the two: yield strength 600 MPa (87 ksi) against 541 MPa (78.5 ksi) for Stellite 6, about 11% more. In exchange, Stellite 6 is the more ductile: elongation 1% versus 0.5% for Stellite 3, and Stellite 3 is harder (55 HRC vs 40 HRC). On the shop floor, Stellite 6 welds better (good vs poor) and Stellite 3 sits in a lower cost tier (high, $$$$) than Stellite 6 (specialty, $$$$$).
Stellite 3Choose it when strength drives the design, or when cost is the deciding factor.
Stellite 6Choose it when the part is bent, formed or impact-loaded, or when it will be welded.
Stellite 3 vs Stellite 6: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all cobalt-chrome alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all cobalt-chrome alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
Bulk Modulus
Same in both: Poisson's Ratio 0.3
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Min Service Temperature
Same in both: Max Service Temperature (continuous) 800°C1,472 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.25 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Same in both: Thermal Shock Resistance Index 4
Strength versus weight
Yield strength against density for every cobalt-chrome alloy grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | Stellite 3 | Stellite 6 |
|---|---|---|
| Default condition | — | As Cast |
| Relative cost | $$$$ High | $$$$$ Specialty |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Stellite 3 vs Stellite 6 — frequently asked
Is Stellite 3 stronger than Stellite 6?
Yes. Stellite 3 has a typical yield strength of 600 MPa (87 ksi) against 541 MPa (78.5 ksi) for Stellite 6 — about 11% more. Tensile strength is 620 MPa (89.9 ksi) vs 834 MPa (121 ksi).
Which is cheaper, Stellite 3 or Stellite 6?
Stellite 3 is the lower-cost material: it sits in the high tier ($$$$) while Stellite 6 is specialty ($$$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which welds better, Stellite 3 or Stellite 6?
Stellite 6. Its weldability rates good (55/100) against poor (20/100) for Stellite 3.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Stellite 3 and Stellite 6 side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.