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Titanium C-9 vs Grade C-6

Titanium · grade comparison

Titanium C-9 and Grade C-6 are both titanium grades. Grade C-6 is the stronger of the two: yield strength 800 MPa (116 ksi) against 550 MPa (79.8 ksi) for C-9, about 45% more; tensile strength follows at 860 MPa (125 ksi) vs 690 MPa (100 ksi). Grade C-6 is harder — 295 HB against 240 HB for C-9 — which matters for wear surfaces and threads. Grade C-6 is stiffer (110 GPa vs 100 GPa) and Grade C-6 runs hotter in service (480°C vs 300°C continuous).

Grade C-6Choose it when strength drives the design, or when surface hardness matters.

C-9 vs Grade C-6: properties

C-9Grade C-6

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

100 GPa14.5 Msi
110 GPa16 Msi

Poisson's Ratio

0.3
0.31

Tensile Strength (Ultimate)

690 MPa100 ksi
860 MPa125 ksi

Yield Strength (0.2% offset)

550 MPa79.8 ksi
800 MPa116 ksi

Reduction in Area

20%
22%

Compressive Strength

620 MPa89.9 ksi
880 MPa128 ksi

Shear Strength

450 MPa65.3 ksi
590 MPa85.6 ksi

Fatigue Strength (Endurance Limit)

340 MPa49.3 ksi
450 MPa65.3 ksi

Fracture Toughness (K_IC)

70 MPa·√m63.7 ksi·√in
75 MPa·√m68.3 ksi·√in

Charpy V-Notch Impact (RT)

22 J16.2 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

240 HB
295 HB

Hardness, Rockwell C

23 HRC
31 HRC

Hardness, Vickers

255 HV
315 HV

Same in both: Shear Modulus 44 GPa6.4 Msi · Bulk Modulus 110 GPa16 Msi · Elongation at Break 12%

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,650°C3,002 °F
1,540°C2,804 °F

Liquidus Temperature

1,700°C3,092 °F
1,620°C2,948 °F

Same in both: Density 4.48 g/cm³0.16 lb/in³

Thermal

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

Thermal Conductivity

7.6 W/m·K4.4 BTU/hr·ft·°F
7.8 W/m·K4.5 BTU/hr·ft·°F

Specific Heat Capacity

544 J/kg·K0.13 BTU/lb·°F
500 J/kg·K0.12 BTU/lb·°F

Latent Heat of Fusion

365 J/g157 BTU/lb
325 J/g140 BTU/lb

Max Service Temperature (continuous)

300°C572 °F
480°C896 °F

Same in both: Thermal Expansion (CTE, 20–100 °C) 9.4 µm/m·K5.2 µin/in·°F · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

1.4 % IACS
1.1 % IACS

Electrical Resistivity

1.26×10⁻⁶ Ω·m49.6 µΩ·in
1.57×10⁻⁶ Ω·m61.8 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

92 / 100
88 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.1 V

Manufacturability

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

Machinability

25 / 100
22 / 100

Formability (cold)

10 / 100
15 / 100

Castability

70 / 100
62 / 100

Brazeability / Solderability

35 / 100
40 / 100

Polishability

70 / 100
60 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 22% · Weldability 80 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

650 MJ/kg279,450 BTU/lb
680 MJ/kg292,348 BTU/lb

Embodied Carbon (primary production)

42 kg CO₂/kg
45 kg CO₂/kg

Typical Recycled Content

35%
25%

Same in both: Embodied Water 450 L/kg53.9 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

154 kN·m/kg
192 kN·m/kg

Specific Stiffness (E / density)

22.3 MN·m/kg
24.6 MN·m/kg

Modulus of Resilience

1,513 kJ/m³
2,909 kJ/m³

Thermal Diffusivity

3.1 mm²/s
3.5 mm²/s

Same in both: Thermal Shock Resistance Index 6

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 scaleC-9Grade C-6

Manufacturing and finishing

CapabilityC-9Grade C-6
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

Both take the same 1 finish: Plasma Spray.

C-9 vs Grade C-6 — frequently asked

Is Grade C-6 stronger than C-9?

Yes. Grade C-6 has a typical yield strength of 800 MPa (116 ksi) against 550 MPa (79.8 ksi) for C-9 — about 45% more. Tensile strength is 860 MPa (125 ksi) vs 690 MPa (100 ksi).

Which is cheaper, C-9 or Grade C-6?

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.

When should I choose C-9 over Grade C-6?

Pick Grade C-6 when strength drives the design, or when surface hardness matters.

Ready to make it?

Upload a CAD file and FabDigit prices the part in C-9 and Grade C-6 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.