Refractory Metal ZIRLO vs Zr 704C
Refractory Metal · grade comparison
Refractory Metal ZIRLO and Zr 704C are both refractory metal grades. ZIRLO is the stronger of the two: yield strength 530 MPa (76.9 ksi) against 300 MPa (43.5 ksi) for Zr 704C, about 77% more; tensile strength follows at 650 MPa (94.3 ksi) vs 450 MPa (65.3 ksi). ZIRLO is the more ductile: elongation 16% versus 13% for Zr 704C. ZIRLO conducts heat better (14.5 W/m·K vs 13 W/m·K).
ZIRLOChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
ZIRLO vs Zr 704C: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all refractory metal 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 refractory metal 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.
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, Rockwell B
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 99 GPa14.4 Msi · Shear Modulus 36 GPa5.2 Msi · Hardness, Brinell 190 HB
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
Min Service Temperature
Same in both: Specific Heat Capacity 285 J/kg·K0.07 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 6 µm/m·K3.3 µin/in·°F · Latent Heat of Fusion 155 J/g66.6 BTU/lb · Max Service Temperature (continuous) 400°C752 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
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 60 / 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)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Same in both: Specific Stiffness (E / density) 15.1 MN·m/kg
Strength versus weight
Yield strength against density for every refractory metal grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | ZIRLO | Zr 704C |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
ZIRLO vs Zr 704C — frequently asked
Is ZIRLO stronger than Zr 704C?
Yes. ZIRLO has a typical yield strength of 530 MPa (76.9 ksi) against 300 MPa (43.5 ksi) for Zr 704C — about 77% more. Tensile strength is 650 MPa (94.3 ksi) vs 450 MPa (65.3 ksi).
Which is cheaper, ZIRLO or Zr 704C?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
When should I choose ZIRLO over Zr 704C?
Pick ZIRLO when strength drives the design, or when the part is bent, formed or impact-loaded.
Ready to make it?
Upload a CAD file and FabDigit prices the part in ZIRLO and Zr 704C 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.