FabDigitFabDigit

Refractory Metal Zircaloy-2 vs Zr 702

Refractory Metal · grade comparison

Refractory Metal Zircaloy-2 and Zr 702 are both refractory metal grades. Zircaloy-2 is the stronger of the two: yield strength 320 MPa (46.4 ksi) against 290 MPa (42.1 ksi) for Zr 702, about 10% more; tensile strength follows at 490 MPa (71.1 ksi) vs 450 MPa (65.3 ksi). In exchange, Zr 702 is the more ductile: elongation 30% versus 27% for Zircaloy-2, and Zircaloy-2 is harder (180 HB vs 150 HB). Zr 702 conducts heat better (22 W/m·K vs 13.5 W/m·K). On the shop floor, Zr 702 welds better (80 vs 70 out of 100).

Zircaloy-2Choose it when strength drives the design.

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

Zircaloy-2 vs Zr 702: properties

Zircaloy-2Zr 702

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

97 GPa14.1 Msi
99 GPa14.4 Msi

Bulk Modulus

96 GPa13.9 Msi
92 GPa13.3 Msi

Poisson's Ratio

0.37
0.35

Tensile Strength (Ultimate)

490 MPa71.1 ksi
450 MPa65.3 ksi

Yield Strength (0.2% offset)

320 MPa46.4 ksi
290 MPa42.1 ksi

Elongation at Break

27%
30%

Reduction in Area

40%
45%

Compressive Strength

330 MPa47.9 ksi
300 MPa43.5 ksi

Shear Strength

300 MPa43.5 ksi
290 MPa42.1 ksi

Fatigue Strength (Endurance Limit)

240 MPa34.8 ksi
230 MPa33.4 ksi

Fracture Toughness (K_IC)

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

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
60 J44.3 ft·lbf

Hardness, Brinell

180 HB
150 HB

Hardness, Rockwell B

89 HRB
85 HRB

Hardness, Vickers

190 HV
160 HV

Same in both: Shear Modulus 36 GPa5.2 Msi

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,760°C3,200 °F
1,852°C3,366 °F

Liquidus Temperature

1,850°C3,362 °F
1,852°C3,366 °F

Thermal

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

Thermal Conductivity

13.5 W/m·K7.8 BTU/hr·ft·°F
22 W/m·K12.7 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

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

Latent Heat of Fusion

225 J/g96.7 BTU/lb
153 J/g65.8 BTU/lb

Max Service Temperature (continuous)

400°C752 °F
371°C700 °F

Min Service Temperature

-200°C-328 °F
-196°C-321 °F

Same in both: Specific Heat Capacity 285 J/kg·K0.07 BTU/lb·°F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.3 % IACS
4.3 % IACS

Electrical Resistivity

7.4×10⁻⁷ Ω·m29.1 µΩ·in
4×10⁻⁷ Ω·m15.7 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.15 V
-0.2 V

Corrosion Resistance

90 / 100
92 / 100

Manufacturability

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

Machinability Rating (AISI 1212 = 100 %)

25%
30%

Weldability

70 / 100
80 / 100

Formability (cold)

60 / 100
70 / 100

Castability

20 / 100
30 / 100

Polishability

60 / 100
70 / 100

Same in both: Machinability 35 / 100 · Brazeability / Solderability 25 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

1,300 MJ/kg558,900 BTU/lb
1,250 MJ/kg537,404 BTU/lb

Typical Recycled Content

5%
15%

Embodied Water

—
900 L/kg108 gal/lb

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

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

75 kN·m/kg
69 kN·m/kg

Specific Stiffness (E / density)

14.8 MN·m/kg
15.2 MN·m/kg

Modulus of Resilience

528 kJ/m³
425 kJ/m³

Thermal Diffusivity

7.2 mm²/s
11.9 mm²/s

Thermal Shock Resistance Index

11
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 702Zircaloy-2

Manufacturing and finishing

CapabilityZircaloy-2Zr 702
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

Zircaloy-2 vs Zr 702 — frequently asked

Is Zircaloy-2 stronger than Zr 702?

Yes. Zircaloy-2 has a typical yield strength of 320 MPa (46.4 ksi) against 290 MPa (42.1 ksi) for Zr 702 — about 10% more. Tensile strength is 490 MPa (71.1 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, Zircaloy-2 or Zr 702?

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, Zircaloy-2 or Zr 702?

Zr 702. Its weldability rates very good (80/100) against very good (70/100) for Zircaloy-2.

Ready to make it?

Upload a CAD file and FabDigit prices the part in Zircaloy-2 and Zr 702 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.