Titanium Grade 3 vs Ti Grade 21
Titanium · grade comparison
Titanium Grade 3 and Ti Grade 21 are both titanium grades. Ti Grade 21 is the stronger of the two: yield strength 805 MPa (117 ksi) against 420 MPa (60.9 ksi) for Grade 3, about 92% more; tensile strength follows at 830 MPa (120 ksi) vs 500 MPa (72.5 ksi). In exchange, Grade 3 is the more ductile: elongation 20% versus 18% for Ti Grade 21, and Ti Grade 21 is harder (285 HV vs 210 HV). Grade 3 is lighter (4.51 g/cm³ vs 4.94 g/cm³ for Ti Grade 21) and Grade 3 is stiffer (103 GPa vs 79 GPa). On the shop floor, Grade 3 machines more easily (fair vs poor), Grade 3 welds better (excellent vs very good), and Ti Grade 21 sits in a lower cost tier (high, $$$$) than Grade 3 (specialty, $$$$$).
Grade 3Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
Ti Grade 21Choose it when strength drives the design, or when the part sees heat.
Grade 3 vs Ti Grade 21: 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 B
Hardness, Vickers
Hardness, Rockwell C
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)
Same in both: Thermal Expansion (CTE, 20–100 °C) 8.6 µm/m·K4.8 µin/in·°F · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.1 V · Corrosion Resistance 92 / 100
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
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 9
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 3 | Ti Grade 21 |
|---|---|---|
| CNC machining | Yes | — |
| Sheet metal | Yes | — |
| Default condition | O | — |
| Relative cost | $$$$$ Specialty | $$$$ High |
| Min. machined wall | 1 mm | — |
| Best machined surface | Ra 1.6 µm | — |
| AlCrN | Yes | — |
| AlTiN | Yes | — |
| Anodizing Type II | Yes | — |
| CVD Al2O3 | Yes | — |
| CVD TiCN | Yes | — |
| CVD TiN | Yes | — |
| Cerakote | Yes | — |
| CrN | Yes | — |
| DLC | Yes | — |
| Electropolishing | Yes | — |
| HVOF Coating | Yes | — |
| MoS2 | Yes | — |
| Multilayer CVD | Yes | — |
| TiAlN | Yes | — |
| TiB2 | Yes | — |
| TiCN | Yes | — |
| TiN | Yes | — |
| WC/C | Yes | — |
They share 1 finish: Plasma Spray.
Grade 3 vs Ti Grade 21 — frequently asked
Is Ti Grade 21 stronger than Grade 3?
Yes. Ti Grade 21 has a typical yield strength of 805 MPa (117 ksi) against 420 MPa (60.9 ksi) for Grade 3 — about 92% more. Tensile strength is 830 MPa (120 ksi) vs 500 MPa (72.5 ksi).
Which is cheaper, Grade 3 or Ti Grade 21?
Ti Grade 21 is the lower-cost material: it sits in the high tier ($$$$) while Grade 3 is specialty ($$$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which is easier to machine, Grade 3 or Ti Grade 21?
Grade 3. Its machinability rates fair (35/100) against poor (20/100) for Ti Grade 21; for welding the order is Grade 3 first (excellent, 85/100) then Ti Grade 21 (very good, 75/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in Grade 3 and Ti Grade 21 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.