Titanium IMI 550-ANN vs IMI 550-STA
Titanium · IMI 550 temper comparison
IMI 550-ANN and IMI 550-STA are two conditions of the same titanium grade, IMI 550: ANN (annealed) versus STA (solution treated and aged). The chemistry is identical, so every difference below comes from the condition. IMI 550-STA is the stronger of the two: yield strength 1,050 MPa (152 ksi) against 900 MPa (131 ksi) for IMI 550-ANN, about 17% more; tensile strength follows at 1,150 MPa (167 ksi) vs 1,000 MPa (145 ksi). In exchange, IMI 550-ANN is the more ductile: elongation 16% versus 13% for IMI 550-STA, and IMI 550-STA is harder (36 HRC vs 32 HRC). IMI 550-STA runs hotter in service (400°C vs 350°C continuous).
IMI 550-ANNChoose it when the part is bent, formed or impact-loaded.
IMI 550-STAChoose it when strength drives the design, or when the part sees heat.
IMI 550-ANN vs IMI 550-STA: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all titanium 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 titanium 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
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 115 GPa16.7 Msi · Shear Modulus 44 GPa6.4 Msi · Bulk Modulus 107 GPa15.5 Msi · Poisson's Ratio 0.32 · Compressive Strength 1,120 MPa162 ksi · Shear Strength 690 MPa100 ksi · Fatigue Strength (Endurance Limit) 580 MPa84.1 ksi · Hardness, Brinell 333 HB
Physical
Density and transition temperatures.
Same in both: Density 4.6 g/cm³0.17 lb/in³ · Melting Point (Solidus) 1,590°C2,894 °F · Liquidus Temperature 1,650°C3,002 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 7.1 W/m·K4.1 BTU/hr·ft·°F · Specific Heat Capacity 565 J/kg·K0.13 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 9.4 µm/m·K5.2 µin/in·°F · Latent Heat of Fusion 365 J/g157 BTU/lb · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 1.1 % IACS · Electrical Resistivity 1.65×10⁻⁶ Ω·m65 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.1 V · Corrosion Resistance 85 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Same in both: Machinability Rating (AISI 1212 = 100 %) 18% · Weldability 25 / 100 · Formability (cold) 15 / 100 · Castability 20 / 100 · Brazeability / Solderability 35 / 100 · Polishability 70 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 650 MJ/kg279,450 BTU/lb · Embodied Carbon (primary production) 42 kg CO₂/kg · Embodied Water 500 L/kg59.9 gal/lb · Typical Recycled Content 20%
Strength versus weight
Yield strength against density for every titanium grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
IMI 550-ANN vs IMI 550-STA — frequently asked
Is IMI 550-STA stronger than IMI 550-ANN?
Yes. IMI 550-STA has a typical yield strength of 1,050 MPa (152 ksi) against 900 MPa (131 ksi) for IMI 550-ANN — about 17% more. Tensile strength is 1,150 MPa (167 ksi) vs 1,000 MPa (145 ksi).
Which condition does FabDigit quote by default, ANN or STA?
STA is the default IMI 550 condition in the FabDigit quote flow. 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 IMI 550-ANN over IMI 550-STA?
Pick IMI 550-ANN when the part is bent, formed or impact-loaded. Pick IMI 550-STA when strength drives the design, or when the part sees heat.
Ready to make it?
Upload a CAD file and FabDigit prices the part in IMI 550-ANN and IMI 550-STA 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.