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Cobalt-Chrome Alloy ERCoCr-A vs Tribaloy T-400

Cobalt-Chrome Alloy · grade comparison

Cobalt-Chrome Alloy ERCoCr-A and Tribaloy T-400 are both cobalt-chrome alloy grades. ERCoCr-A is the stronger of the two: tensile strength 830 MPa (120 ksi) against 690 MPa (100 ksi) for Tribaloy T-400, about 20% more. ERCoCr-A is the more ductile: elongation 1% versus 0.5% for Tribaloy T-400, and Tribaloy T-400 is harder (600 HB vs 390 HB). Tribaloy T-400 is stiffer (225 GPa vs 210 GPa). On the shop floor, ERCoCr-A welds better (good vs fair).

ERCoCr-AChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.

ERCoCr-A vs Tribaloy T-400: properties

ERCoCr-ATribaloy T-400

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
225 GPa32.6 Msi

Shear Modulus

81 GPa11.7 Msi
88 GPa12.8 Msi

Bulk Modulus

175 GPa25.4 Msi
188 GPa27.3 Msi

Tensile Strength (Ultimate)

830 MPa120 ksi
690 MPa100 ksi

Elongation at Break

1%
0.5%

Compressive Strength

1,500 MPa218 ksi
1,900 MPa276 ksi

Shear Strength

540 MPa78.3 ksi
550 MPa79.8 ksi

Fatigue Strength (Endurance Limit)

270 MPa39.2 ksi
300 MPa43.5 ksi

Fracture Toughness (K_IC)

35 MPa·√m31.9 ksi·√in
14 MPa·√m12.7 ksi·√in

Charpy V-Notch Impact (RT)

8 J5.9 ft·lbf
3 J2.2 ft·lbf

Hardness, Brinell

390 HB
600 HB

Hardness, Rockwell C

41 HRC
56 HRC

Hardness, Vickers

430 HV
640 HV

Reduction in Area

—
0.5%

Same in both: Poisson's Ratio 0.3 · Yield Strength (0.2% offset) 620 MPa89.9 ksi

Physical

Density and transition temperatures.

Density

8.44 g/cm³0.3 lb/in³
8.61 g/cm³0.31 lb/in³

Melting Point (Solidus)

1,285°C2,345 °F
1,245°C2,273 °F

Liquidus Temperature

1,395°C2,543 °F
1,300°C2,372 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

14.8 W/m·K8.6 BTU/hr·ft·°F
14 W/m·K8.1 BTU/hr·ft·°F

Specific Heat Capacity

423 J/kg·K0.1 BTU/lb·°F
420 J/kg·K0.1 BTU/lb·°F

Max Service Temperature (continuous)

800°C1,472 °F
760°C1,400 °F

Same in both: Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

2 % IACS
1.8 % IACS

Electrical Resistivity

8.8×10⁻⁷ Ω·m34.6 µΩ·in
9.5×10⁻⁷ Ω·m37.4 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.25 V
-0.15 V

Corrosion Resistance

78 / 100
68 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

8 / 100
5 / 100

Machinability Rating (AISI 1212 = 100 %)

5%
3%

Weldability

55 / 100
35 / 100

Formability (cold)

3 / 100
2 / 100

Castability

70 / 100
60 / 100

Brazeability / Solderability

55 / 100
45 / 100

Same in both: Polishability 80 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

155 MJ/kg66,638 BTU/lb
190 MJ/kg81,685 BTU/lb

Embodied Carbon (primary production)

11.5 kg CO₂/kg
16 kg CO₂/kg

Embodied Water

350 L/kg41.9 gal/lb
400 L/kg47.9 gal/lb

Typical Recycled Content

25%
20%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

98 kN·m/kg
80 kN·m/kg

Specific Stiffness (E / density)

24.9 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

915 kJ/m³
854 kJ/m³

Thermal Diffusivity

4.1 mm²/s
3.9 mm²/s

Thermal Shock Resistance Index

5
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.

5007001,0001,5002,0008.28.48.68.89Density (g/cm³)Yield strength (MPa) — log scaleTribaloy T-400ERCoCr-A

Manufacturing and finishing

CapabilityERCoCr-ATribaloy T-400
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

ERCoCr-A vs Tribaloy T-400 — frequently asked

Is ERCoCr-A stronger than Tribaloy T-400?

Yes. ERCoCr-A has a typical tensile strength of 830 MPa (120 ksi) against 690 MPa (100 ksi) for Tribaloy T-400 — about 20% more.

Which is cheaper, ERCoCr-A or Tribaloy T-400?

Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which welds better, ERCoCr-A or Tribaloy T-400?

ERCoCr-A. Its weldability rates good (55/100) against fair (35/100) for Tribaloy T-400.

Ready to make it?

Upload a CAD file and FabDigit prices the part in ERCoCr-A and Tribaloy T-400 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.