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Titanium Grade 17 vs IMI 829

Titanium · grade comparison

Titanium Grade 17 and IMI 829 are both titanium grades. IMI 829 is the stronger of the two: yield strength 865 MPa (125 ksi) against 240 MPa (34.8 ksi) for Grade 17, about 3.6 times as much; tensile strength follows at 980 MPa (142 ksi) vs 330 MPa (47.9 ksi). In exchange, Grade 17 is the more ductile: elongation 32% versus 11% for IMI 829, and IMI 829 is harder (313 HB vs 120 HB). IMI 829 is stiffer (120 GPa vs 103 GPa) and IMI 829 runs hotter in service (580°C vs 315°C continuous). On the shop floor, Grade 17 machines more easily (fair vs poor) and Grade 17 welds better (excellent vs fair).

Grade 17Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

IMI 829Choose it when strength drives the design, or when the part sees heat.

Grade 17 vs IMI 829: properties

Grade 17IMI 829

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

103 GPa14.9 Msi
120 GPa17.4 Msi

Poisson's Ratio

0.34
0.32

Tensile Strength (Ultimate)

330 MPa47.9 ksi
980 MPa142 ksi

Yield Strength (0.2% offset)

240 MPa34.8 ksi
865 MPa125 ksi

Elongation at Break

32%
11%

Reduction in Area

58%
20%

Compressive Strength

300 MPa43.5 ksi
900 MPa131 ksi

Shear Strength

250 MPa36.3 ksi
620 MPa89.9 ksi

Fatigue Strength (Endurance Limit)

175 MPa25.4 ksi
500 MPa72.5 ksi

Fracture Toughness (K_IC)

80 MPa·√m72.8 ksi·√in
70 MPa·√m63.7 ksi·√in

Charpy V-Notch Impact (RT)

90 J66.4 ft·lbf
16 J11.8 ft·lbf

Hardness, Brinell

120 HB
313 HB

Hardness, Rockwell B

70 HRB
—

Hardness, Vickers

125 HV
330 HV

Hardness, Rockwell C

—
33 HRC

Same in both: Shear Modulus 45 GPa6.5 Msi · Bulk Modulus 110 GPa16 Msi

Physical

Density and transition temperatures.

Density

4.51 g/cm³0.16 lb/in³
4.54 g/cm³0.16 lb/in³

Melting Point (Solidus)

1,660°C3,020 °F
1,550°C2,822 °F

Liquidus Temperature

1,670°C3,038 °F
1,630°C2,966 °F

Thermal

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

Thermal Conductivity

17.5 W/m·K10.1 BTU/hr·ft·°F
7 W/m·K4 BTU/hr·ft·°F

Specific Heat Capacity

523 J/kg·K0.12 BTU/lb·°F
530 J/kg·K0.13 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

8.6 µm/m·K4.8 µin/in·°F
9.5 µm/m·K5.3 µin/in·°F

Latent Heat of Fusion

419 J/g180 BTU/lb
390 J/g168 BTU/lb

Max Service Temperature (continuous)

315°C599 °F
580°C1,076 °F

Min Service Temperature

-250°C-418 °F
-196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

3.3 % IACS
1.1 % IACS

Electrical Resistivity

5.2×10⁻⁷ Ω·m20.5 µΩ·in
1.6×10⁻⁶ Ω·m63 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

95 / 100
85 / 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

40 / 100
15 / 100

Machinability Rating (AISI 1212 = 100 %)

35%
18%

Weldability

88 / 100
45 / 100

Formability (cold)

90 / 100
20 / 100

Brazeability / Solderability

45 / 100
40 / 100

Polishability

70 / 100
65 / 100

Castability

—
30 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

42 kg CO₂/kg
43 kg CO₂/kg

Embodied Water

900 L/kg108 gal/lb
500 L/kg59.9 gal/lb

Typical Recycled Content

25%
15%

Same in both: Embodied Energy (primary production) 700 MJ/kg300,946 BTU/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

73 kN·m/kg
216 kN·m/kg

Specific Stiffness (E / density)

22.8 MN·m/kg
26.4 MN·m/kg

Modulus of Resilience

280 kJ/m³
3,118 kJ/m³

Thermal Diffusivity

7.4 mm²/s
2.9 mm²/s

Thermal Shock Resistance Index

7
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 scaleGrade 17IMI 829

Manufacturing and finishing

CapabilityGrade 17IMI 829
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

Both take the same 1 finish: Plasma Spray.

Grade 17 vs IMI 829 — frequently asked

Is IMI 829 stronger than Grade 17?

Yes. IMI 829 has a typical yield strength of 865 MPa (125 ksi) against 240 MPa (34.8 ksi) for Grade 17 — about 3.6 times as much. Tensile strength is 980 MPa (142 ksi) vs 330 MPa (47.9 ksi).

Which is cheaper, Grade 17 or IMI 829?

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.

Which is easier to machine, Grade 17 or IMI 829?

Grade 17. Its machinability rates fair (40/100) against poor (15/100) for IMI 829; for welding the order is Grade 17 first (excellent, 88/100) then IMI 829 (fair, 45/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in Grade 17 and IMI 829 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.