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Titanium IMI 550 FORGED-STA vs IMI 550-HR

Titanium · IMI 550 temper comparison

IMI 550 FORGED-STA and IMI 550-HR are two conditions of the same titanium grade, IMI 550: FORGED-STA versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. IMI 550 FORGED-STA is the stronger of the two: yield strength 1,030 MPa (149 ksi) against 950 MPa (138 ksi) for IMI 550-HR, about 8% more; tensile strength follows at 1,130 MPa (164 ksi) vs 1,050 MPa (152 ksi). IMI 550 FORGED-STA is harder — 35 HRC against 33 HRC for IMI 550-HR — which matters for wear surfaces and threads. IMI 550 FORGED-STA runs hotter in service (400°C vs 350°C continuous).

IMI 550 FORGED-STAChoose it when strength drives the design, or when surface hardness matters.

IMI 550 FORGED-STA vs IMI 550-HR: properties

IMI 550 FORGED-STAIMI 550-HR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

115 GPa16.7 Msi
114 GPa16.5 Msi

Tensile Strength (Ultimate)

1,130 MPa164 ksi
1,050 MPa152 ksi

Yield Strength (0.2% offset)

1,030 MPa149 ksi
950 MPa138 ksi

Compressive Strength

1,100 MPa160 ksi
1,010 MPa146 ksi

Shear Strength

680 MPa98.6 ksi
640 MPa92.8 ksi

Fatigue Strength (Endurance Limit)

570 MPa82.7 ksi
510 MPa74 ksi

Fracture Toughness (K_IC)

45 MPa·√m41 ksi·√in
52 MPa·√m47.3 ksi·√in

Charpy V-Notch Impact (RT)

14 J10.3 ft·lbf
18 J13.3 ft·lbf

Hardness, Brinell

328 HB
313 HB

Hardness, Rockwell C

35 HRC
33 HRC

Hardness, Vickers

345 HV
330 HV

Same in both: Shear Modulus 44 GPa6.4 Msi · Bulk Modulus 107 GPa15.5 Msi · Poisson's Ratio 0.32 · Elongation at Break 12% · Reduction in Area 28%

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.

Thermal Conductivity

7.1 W/m·K4.1 BTU/hr·ft·°F
7.2 W/m·K4.2 BTU/hr·ft·°F

Max Service Temperature (continuous)

400°C752 °F
350°C662 °F

Same in both: 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

16 / 100
18 / 100

Machinability Rating (AISI 1212 = 100 %)

18%
20%

Weldability

25 / 100
30 / 100

Formability (cold)

15 / 100
18 / 100

Same in both: 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.

3005007001,0004.555.5Density (g/cm³)Yield strength (MPa) — log scaleIMI 550

IMI 550 FORGED-STA vs IMI 550-HR — frequently asked

Is IMI 550 FORGED-STA stronger than IMI 550-HR?

Yes. IMI 550 FORGED-STA has a typical yield strength of 1,030 MPa (149 ksi) against 950 MPa (138 ksi) for IMI 550-HR — about 8% more. Tensile strength is 1,130 MPa (164 ksi) vs 1,050 MPa (152 ksi).

Which condition does FabDigit quote by default, FORGED-STA or HR?

STA is the default IMI 550 condition in the FabDigit quote flow (neither FORGED-STA nor HR). 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 welds better, IMI 550 FORGED-STA or IMI 550-HR?

IMI 550-HR. Its weldability rates poor (30/100) against poor (25/100) for IMI 550 FORGED-STA.

Ready to make it?

Upload a CAD file and FabDigit prices the part in IMI 550 FORGED-STA and IMI 550-HR 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.