Titanium Grade 17 vs OT4
Titanium · grade comparison
Titanium Grade 17 and OT4 are both titanium grades. OT4 is the stronger of the two: yield strength 640 MPa (92.8 ksi) against 240 MPa (34.8 ksi) for Grade 17, about 167% more; tensile strength follows at 780 MPa (113 ksi) vs 330 MPa (47.9 ksi). In exchange, Grade 17 is the more ductile: elongation 32% versus 16% for OT4, and OT4 is harder (240 HB vs 120 HB). OT4 is stiffer (115 GPa vs 103 GPa) and OT4 runs hotter in service (350°C vs 315°C continuous). On the shop floor, Grade 17 machines more easily (fair vs poor) and Grade 17 welds better (excellent vs very good).
Grade 17Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
OT4Choose it when strength drives the design, or when the part sees heat.
Grade 17 vs OT4: 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.
Elastic (Young's) Modulus
Shear Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Hardness, Rockwell C
Same in both: Bulk Modulus 110 GPa16 Msi
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Thermal Expansion (CTE, 20–100 °C) 8.6 µm/m·K4.8 µin/in·°F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
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
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Polishability
Same in both: Brazeability / Solderability 45 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Same in both: Typical Recycled Content 25%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Same in both: Thermal Shock Resistance Index 7
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.
Manufacturing and finishing
| Capability | Grade 17 | OT4 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both take the same 1 finish: Plasma Spray.
Grade 17 vs OT4 — frequently asked
Is OT4 stronger than Grade 17?
Yes. OT4 has a typical yield strength of 640 MPa (92.8 ksi) against 240 MPa (34.8 ksi) for Grade 17 — about 167% more. Tensile strength is 780 MPa (113 ksi) vs 330 MPa (47.9 ksi).
Which is cheaper, Grade 17 or OT4?
Both sit in the same relative cost tier ($$$$, 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 OT4?
Grade 17. Its machinability rates fair (40/100) against poor (28/100) for OT4; for welding the order is Grade 17 first (excellent, 88/100) then OT4 (very good, 72/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in Grade 17 and OT4 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.