Titanium Grade 9 vs TC21
Titanium · grade comparison
Titanium Grade 9 and TC21 are both titanium grades. TC21 is the stronger of the two: yield strength 1,060 MPa (154 ksi) against 570 MPa (82.7 ksi) for Grade 9, about 86% more; tensile strength follows at 1,150 MPa (167 ksi) vs 690 MPa (100 ksi). In exchange, Grade 9 is the more ductile: elongation 20% versus 10% for TC21, and TC21 is harder (350 HB vs 250 HB). TC21 is stiffer (114 GPa vs 100 GPa) and TC21 runs hotter in service (350°C vs 300°C continuous). On the shop floor, Grade 9 machines more easily (28 vs 16 out of 100) and Grade 9 welds better (very good vs fair).
Grade 9Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
TC21Choose it when strength drives the design, or when the part sees heat.
Grade 9 vs TC21: 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
Bulk 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 C
Hardness, Vickers
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
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Latent Heat of Fusion 365 J/g157 BTU/lb
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)
Castability
Brazeability / Solderability
Same in both: Polishability 70 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
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 9 | TC21 |
|---|---|---|
| CNC machining | Yes | — |
| Sheet metal | Yes | — |
| Default condition | O | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | 1 mm | — |
| Best machined surface | Ra 1.6 µm | — |
| AlCrN | Yes | — |
| AlTiN | Yes | — |
| Anodizing Type II | Yes | — |
| CVD Al2O3 | Yes | — |
| CVD TiCN | Yes | — |
| CVD TiN | Yes | — |
| Cerakote | Yes | — |
| CrN | Yes | — |
| DLC | Yes | — |
| Electropolishing | Yes | — |
| HVOF Coating | Yes | — |
| MoS2 | Yes | — |
| Multilayer CVD | Yes | — |
| TiAlN | Yes | — |
| TiB2 | Yes | — |
| TiCN | Yes | — |
| TiN | Yes | — |
| WC/C | Yes | — |
They share 1 finish: Plasma Spray.
Grade 9 vs TC21 — frequently asked
Is TC21 stronger than Grade 9?
Yes. TC21 has a typical yield strength of 1,060 MPa (154 ksi) against 570 MPa (82.7 ksi) for Grade 9 — about 86% more. Tensile strength is 1,150 MPa (167 ksi) vs 690 MPa (100 ksi).
Which is cheaper, Grade 9 or TC21?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, Grade 9 or TC21?
Grade 9, by a small margin. Both rate poor for machinability — 28/100 against 16/100 for TC21; for welding the order is Grade 9 first (very good, 80/100) then TC21 (fair, 50/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in Grade 9 and TC21 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.