Refractory Metal Ta-40Nb-CW vs Ta-40Nb-SR
Refractory Metal · Ta-40Nb temper comparison
Ta-40Nb-CW and Ta-40Nb-SR are two conditions of the same refractory metal grade, Ta-40Nb: CW (cold worked) versus SR (stress relieved). The chemistry is identical, so every difference below comes from the condition. Ta-40Nb-CW is the stronger of the two: yield strength 570 MPa (82.7 ksi) against 370 MPa (53.7 ksi) for Ta-40Nb-SR, about 54% more; tensile strength follows at 620 MPa (89.9 ksi) vs 450 MPa (65.3 ksi). In exchange, Ta-40Nb-SR is the more ductile: elongation 15% versus 6% for Ta-40Nb-CW, and Ta-40Nb-CW is harder (215 HB vs 165 HB). Ta-40Nb-SR runs hotter in service (300°C vs 250°C continuous). On the shop floor, Ta-40Nb-SR welds better (80 vs 70 out of 100).
Ta-40Nb-CWChoose it when strength drives the design.
Ta-40Nb-SRChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
Ta-40Nb-CW vs Ta-40Nb-SR: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all refractory metal 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 refractory metal 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.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 138 GPa20 Msi · Shear Modulus 51 GPa7.4 Msi · Bulk Modulus 165 GPa23.9 Msi · Poisson's Ratio 0.36
Physical
Density and transition temperatures.
Same in both: Density 12.1 g/cm³0.44 lb/in³ · Melting Point (Solidus) 2,650°C4,802 °F · Liquidus Temperature 2,750°C4,982 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 190 J/kg·K0.05 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 6.8 µm/m·K3.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -253°C-423 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
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 20 / 100 · Brazeability / Solderability 50 / 100 · Polishability 70 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 2,800 MJ/kg1,203,784 BTU/lb · Embodied Carbon (primary production) 160 kg CO₂/kg · Typical Recycled Content 25%
Strength versus weight
Yield strength against density for every refractory metal grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Ta-40Nb-CW vs Ta-40Nb-SR — frequently asked
Is Ta-40Nb-CW stronger than Ta-40Nb-SR?
Yes. Ta-40Nb-CW has a typical yield strength of 570 MPa (82.7 ksi) against 370 MPa (53.7 ksi) for Ta-40Nb-SR — about 54% more. Tensile strength is 620 MPa (89.9 ksi) vs 450 MPa (65.3 ksi).
Which condition does FabDigit quote by default, CW or SR?
Annealed is the default Ta-40Nb condition in the FabDigit quote flow (neither CW nor SR). 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.
Which is easier to machine, Ta-40Nb-CW or Ta-40Nb-SR?
Ta-40Nb-CW. Its machinability rates fair (35/100) against poor (30/100) for Ta-40Nb-SR; for welding the order is Ta-40Nb-SR first (very good, 80/100) then Ta-40Nb-CW (very good, 70/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in Ta-40Nb-CW and Ta-40Nb-SR 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.