Cobalt-Chrome Alloy Stellite 21 As Welded vs Stellite 21-HIP
Cobalt-Chrome Alloy · Stellite 21 temper comparison
Stellite 21 As Welded and Stellite 21-HIP are two conditions of the same cobalt-chrome alloy grade, Stellite 21: As Welded (as-welded deposit) versus HIP (hot isostatic pressed). The chemistry is identical, so every difference below comes from the condition. Stellite 21-HIP is the stronger of the two: yield strength 640 MPa (92.8 ksi) against 490 MPa (71.1 ksi) for Stellite 21 As Welded, about 31% more; tensile strength follows at 950 MPa (138 ksi) vs 700 MPa (102 ksi). Stellite 21-HIP is the more ductile: elongation 16% versus 8% for Stellite 21 As Welded, and Stellite 21-HIP is harder (320 HB vs 300 HB).
Stellite 21-HIPChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
Stellite 21 As Welded vs Stellite 21-HIP: 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.
Stellite 21 As WeldedStellite 21-HIP
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) 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
Same in both: Shear Modulus 95 GPa13.8 Msi · Bulk Modulus 200 GPa29 Msi · Poisson's Ratio 0.3
Physical
Density and transition temperatures.
Same in both: Density 8.33 g/cm³0.3 lb/in³ · Melting Point (Solidus) 1,186°C2,167 °F · Liquidus Temperature 1,383°C2,521 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 14.8 W/m·K8.6 BTU/hr·ft·°F · Specific Heat Capacity 423 J/kg·K0.1 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 14.2 µm/m·K7.9 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Max Service Temperature (continuous) 760°C1,400 °F · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 2 % IACS · Electrical Resistivity 8.6×10⁻⁷ Ω·m33.9 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.3 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Castability 78 / 100 · Brazeability / Solderability 55 / 100 · Polishability 85 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 145 MJ/kg62,339 BTU/lb · Embodied Carbon (primary production) 10 kg CO₂/kg · Embodied Water 420 L/kg50.3 gal/lb · Typical Recycled Content 25%
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.
Stellite 21 As Welded vs Stellite 21-HIP — frequently asked
Is Stellite 21-HIP stronger than Stellite 21 As Welded?
Yes. Stellite 21-HIP has a typical yield strength of 640 MPa (92.8 ksi) against 490 MPa (71.1 ksi) for Stellite 21 As Welded — about 31% more. Tensile strength is 950 MPa (138 ksi) vs 700 MPa (102 ksi).
Which condition does FabDigit quote by default, As Welded or HIP?
As Cast is the default Stellite 21 condition in the FabDigit quote flow (neither As Welded nor HIP). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.
When should I choose Stellite 21 As Welded over Stellite 21-HIP?
Pick Stellite 21-HIP when strength drives the design, or when the part is bent, formed or impact-loaded.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Stellite 21 As Welded and Stellite 21-HIP 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.