Nickel Alloy Nimonic 80A-ST vs Nimonic 80A STA-HT
Nickel Alloy · Nimonic 80A temper comparison
Nimonic 80A-ST and Nimonic 80A STA-HT are two conditions of the same nickel alloy grade, Nimonic 80A: ST (solution annealed) versus STA-HT (1080 °C/8 h AC + 850 °C/24 h AC stabilise + 700 °C/16 h AC). The chemistry is identical, so every difference below comes from the condition. Nimonic 80A STA-HT is the stronger of the two: yield strength 640 MPa (92.8 ksi) against 320 MPa (46.4 ksi) for Nimonic 80A-ST, about 100% more; tensile strength follows at 1,010 MPa (146 ksi) vs 800 MPa (116 ksi). In exchange, Nimonic 80A-ST is the more ductile: elongation 45% versus 30% for Nimonic 80A STA-HT, and Nimonic 80A STA-HT is harder (290 HB vs 185 HB). Nimonic 80A STA-HT runs hotter in service (870°C vs 700°C continuous). On the shop floor, Nimonic 80A-ST welds better (fair vs poor).
Nimonic 80A-STChoose it when the part is bent, formed or impact-loaded, or when it will be welded.
Nimonic 80A STA-HTChoose it when strength drives the design, or when the part sees heat.
Nimonic 80A-ST vs Nimonic 80A STA-HT: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all nickel 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 nickel 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.
Nimonic 80A-STNimonic 80A STA-HT
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)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 222 GPa32.2 Msi · Shear Modulus 85 GPa12.3 Msi · Bulk Modulus 180 GPa26.1 Msi · Poisson's Ratio 0.31
Physical
Density and transition temperatures.
Same in both: Density 8.19 g/cm³0.3 lb/in³ · Melting Point (Solidus) 1,360°C2,480 °F · Liquidus Temperature 1,390°C2,534 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 11.2 W/m·K6.5 BTU/hr·ft·°F · Specific Heat Capacity 448 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.7 µm/m·K7.1 µin/in·°F · Latent Heat of Fusion 290 J/g125 BTU/lb · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 1.4 % IACS · Electrical Resistivity 1.24×10⁻⁶ Ω·m48.8 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.13 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: Brazeability / Solderability 45 / 100 · Polishability 75 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 200 MJ/kg85,985 BTU/lb · Embodied Carbon (primary production) 13.5 kg CO₂/kg · Embodied Water 1,400 L/kg168 gal/lb · Typical Recycled Content 35%
Strength versus weight
Yield strength against density for every nickel alloy grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Nimonic 80A-ST vs Nimonic 80A STA-HT — frequently asked
Is Nimonic 80A STA-HT stronger than Nimonic 80A-ST?
Yes. Nimonic 80A STA-HT has a typical yield strength of 640 MPa (92.8 ksi) against 320 MPa (46.4 ksi) for Nimonic 80A-ST — about 100% more. Tensile strength is 1,010 MPa (146 ksi) vs 800 MPa (116 ksi).
Which condition does FabDigit quote by default, ST or STA-HT?
STA is the default Nimonic 80A condition in the FabDigit quote flow (neither ST nor STA-HT). 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, Nimonic 80A-ST or Nimonic 80A STA-HT?
Nimonic 80A-ST, by a small margin. Both rate poor for machinability — 22/100 against 16/100 for Nimonic 80A STA-HT; for welding the order is Nimonic 80A-ST first (fair, 45/100) then Nimonic 80A STA-HT (poor, 32/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in Nimonic 80A-ST and Nimonic 80A STA-HT 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.