Titanium ERTi-4 vs ERTi-7
Titanium · grade comparison
Titanium ERTi-4 and ERTi-7 are both titanium grades. ERTi-4 is the stronger of the two: yield strength 550 MPa (79.8 ksi) against 330 MPa (47.9 ksi) for ERTi-7, about 67% more; tensile strength follows at 620 MPa (89.9 ksi) vs 420 MPa (60.9 ksi). In exchange, ERTi-7 is the more ductile: elongation 24% versus 18% for ERTi-4, and ERTi-4 is harder (240 HB vs 155 HB). ERTi-4 runs hotter in service (400°C vs 315°C continuous). On the shop floor, ERTi-7 machines more easily (fair vs poor).
ERTi-4Choose it when strength drives the design, or when the part sees heat.
ERTi-7Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
ERTi-4 vs ERTi-7: 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
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
Same in both: Shear Modulus 45 GPa6.5 Msi · Bulk Modulus 110 GPa16 Msi · Poisson's Ratio 0.34
Physical
Density and transition temperatures.
Same in both: Density 4.51 g/cm³0.16 lb/in³ · Melting Point (Solidus) 1,660°C3,020 °F · Liquidus Temperature 1,670°C3,038 °F
Thermal
How each material carries heat and how hot it can run.
Specific Heat Capacity
Latent Heat of Fusion
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 16.4 W/m·K9.5 BTU/hr·ft·°F · 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).
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
Same in both: Typical Recycled Content 10%
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 | ERTi-4 | ERTi-7 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both take the same 1 finish: Plasma Spray.
ERTi-4 vs ERTi-7 — frequently asked
Is ERTi-4 stronger than ERTi-7?
Yes. ERTi-4 has a typical yield strength of 550 MPa (79.8 ksi) against 330 MPa (47.9 ksi) for ERTi-7 — about 67% more. Tensile strength is 620 MPa (89.9 ksi) vs 420 MPa (60.9 ksi).
Which is cheaper, ERTi-4 or ERTi-7?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, ERTi-4 or ERTi-7?
ERTi-7. Its machinability rates fair (40/100) against poor (28/100) for ERTi-4; for welding the order is ERTi-7 first (excellent, 92/100) then ERTi-4 (excellent, 85/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in ERTi-4 and ERTi-7 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.