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Refractory Metal Zr 702 vs Zr 705

Refractory Metal · grade comparison

Refractory Metal Zr 702 and Zr 705 are both refractory metal grades. Zr 705 is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 290 MPa (42.1 ksi) for Zr 702, about 55% more; tensile strength follows at 620 MPa (89.9 ksi) vs 450 MPa (65.3 ksi). In exchange, Zr 702 is the more ductile: elongation 30% versus 20% for Zr 705, and Zr 705 is harder (200 HB vs 150 HB). Zr 702 conducts heat better (22 W/m·K vs 17.1 W/m·K). On the shop floor, Zr 702 welds better (very good vs good).

Zr 702Choose it when the part is bent, formed or impact-loaded, or when it will be welded.

Zr 705Choose it when strength drives the design.

Zr 702 vs Zr 705: properties

Zr 702Zr 705

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

99 GPa14.4 Msi
97 GPa14.1 Msi

Bulk Modulus

92 GPa13.3 Msi
97 GPa14.1 Msi

Tensile Strength (Ultimate)

450 MPa65.3 ksi
620 MPa89.9 ksi

Yield Strength (0.2% offset)

290 MPa42.1 ksi
450 MPa65.3 ksi

Elongation at Break

30%
20%

Reduction in Area

45%
40%

Compressive Strength

300 MPa43.5 ksi
470 MPa68.2 ksi

Shear Strength

290 MPa42.1 ksi
370 MPa53.7 ksi

Fatigue Strength (Endurance Limit)

230 MPa33.4 ksi
260 MPa37.7 ksi

Fracture Toughness (K_IC)

65 MPa·√m59.2 ksi·√in
60 MPa·√m54.6 ksi·√in

Charpy V-Notch Impact (RT)

60 J44.3 ft·lbf
27 J19.9 ft·lbf

Hardness, Brinell

150 HB
200 HB

Hardness, Rockwell B

85 HRB
95 HRB

Hardness, Vickers

160 HV
210 HV

Same in both: Shear Modulus 36 GPa5.2 Msi · Poisson's Ratio 0.35

Physical

Density and transition temperatures.

Density

6.51 g/cm³0.24 lb/in³
6.64 g/cm³0.24 lb/in³

Melting Point (Solidus)

1,852°C3,366 °F
1,840°C3,344 °F

Liquidus Temperature

1,852°C3,366 °F
—

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

22 W/m·K12.7 BTU/hr·ft·°F
17.1 W/m·K9.9 BTU/hr·ft·°F

Specific Heat Capacity

285 J/kg·K0.07 BTU/lb·°F
281 J/kg·K0.07 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

5.9 µm/m·K3.3 µin/in·°F
6.3 µm/m·K3.5 µin/in·°F

Latent Heat of Fusion

153 J/g65.8 BTU/lb
155 J/g66.6 BTU/lb

Max Service Temperature (continuous)

371°C700 °F
400°C752 °F

Same in both: Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

4.3 % IACS
3.1 % IACS

Electrical Resistivity

4×10⁻⁷ Ω·m15.7 µΩ·in
5.5×10⁻⁷ Ω·m21.7 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.2 V
-0.1 V

Same in both: Corrosion Resistance 92 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability Rating (AISI 1212 = 100 %)

30%
22%

Weldability

80 / 100
65 / 100

Formability (cold)

70 / 100
40 / 100

Castability

30 / 100
25 / 100

Brazeability / Solderability

25 / 100
20 / 100

Same in both: Machinability 35 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

1,250 MJ/kg537,404 BTU/lb
1,400 MJ/kg601,892 BTU/lb

Embodied Water

900 L/kg108 gal/lb
600 L/kg71.9 gal/lb

Typical Recycled Content

15%
25%

Same in both: Embodied Carbon (primary production) 85 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

69 kN·m/kg
93 kN·m/kg

Specific Stiffness (E / density)

15.2 MN·m/kg
14.6 MN·m/kg

Modulus of Resilience

425 kJ/m³
1,044 kJ/m³

Thermal Diffusivity

11.9 mm²/s
9.2 mm²/s

Same in both: Thermal Shock Resistance Index 17

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.

1502003005007001,0001,5005101520Density (g/cm³)Yield strength (MPa) — log scaleZr 702Zr 705

Manufacturing and finishing

CapabilityZr 702Zr 705
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

Zr 702 vs Zr 705 — frequently asked

Is Zr 705 stronger than Zr 702?

Yes. Zr 705 has a typical yield strength of 450 MPa (65.3 ksi) against 290 MPa (42.1 ksi) for Zr 702 — about 55% more. Tensile strength is 620 MPa (89.9 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, Zr 702 or Zr 705?

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 welds better, Zr 702 or Zr 705?

Zr 702. Its weldability rates very good (80/100) against good (65/100) for Zr 705.

Ready to make it?

Upload a CAD file and FabDigit prices the part in Zr 702 and Zr 705 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.