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Refractory Metal Zr 704C vs Zr 705

Refractory Metal · grade comparison

Refractory Metal Zr 704C and Zr 705 are both refractory metal grades. Zr 705 is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 300 MPa (43.5 ksi) for Zr 704C, about 50% more; tensile strength follows at 620 MPa (89.9 ksi) vs 450 MPa (65.3 ksi). Zr 705 is the more ductile: elongation 20% versus 13% for Zr 704C, and Zr 705 is harder (200 HB vs 190 HB). Zr 705 conducts heat better (17.1 W/m·K vs 13 W/m·K).

Zr 705Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

Zr 704C vs Zr 705: properties

Zr 704CZr 705

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

99 GPa14.4 Msi
97 GPa14.1 Msi

Poisson's Ratio

0.34
0.35

Tensile Strength (Ultimate)

450 MPa65.3 ksi
620 MPa89.9 ksi

Yield Strength (0.2% offset)

300 MPa43.5 ksi
450 MPa65.3 ksi

Elongation at Break

13%
20%

Reduction in Area

20%
40%

Compressive Strength

320 MPa46.4 ksi
470 MPa68.2 ksi

Shear Strength

300 MPa43.5 ksi
370 MPa53.7 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
260 MPa37.7 ksi

Fracture Toughness (K_IC)

50 MPa·√m45.5 ksi·√in
60 MPa·√m54.6 ksi·√in

Charpy V-Notch Impact (RT)

20 J14.8 ft·lbf
27 J19.9 ft·lbf

Hardness, Brinell

190 HB
200 HB

Hardness, Rockwell B

89 HRB
95 HRB

Hardness, Vickers

200 HV
210 HV

Same in both: Shear Modulus 36 GPa5.2 Msi · Bulk Modulus 97 GPa14.1 Msi

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,800°C3,272 °F
1,840°C3,344 °F

Liquidus Temperature

1,845°C3,353 °F
—

Thermal

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

Thermal Conductivity

13 W/m·K7.5 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)

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

Min Service Temperature

-75°C-103 °F
-196°C-321 °F

Same in both: Latent Heat of Fusion 155 J/g66.6 BTU/lb · Max Service Temperature (continuous) 400°C752 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.5 % IACS
3.1 % IACS

Electrical Resistivity

6.8×10⁻⁷ Ω·m26.8 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)

-0.15 V
-0.1 V

Corrosion Resistance

90 / 100
92 / 100

Manufacturability

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

Machinability

30 / 100
35 / 100

Machinability Rating (AISI 1212 = 100 %)

28%
22%

Formability (cold)

20 / 100
40 / 100

Castability

55 / 100
25 / 100

Polishability

60 / 100
70 / 100

Same in both: Weldability 65 / 100 · Brazeability / Solderability 20 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

1,200 MJ/kg515,908 BTU/lb
1,400 MJ/kg601,892 BTU/lb

Embodied Carbon (primary production)

75 kg CO₂/kg
85 kg CO₂/kg

Embodied Water

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

Same in both: Typical Recycled Content 25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

69 kN·m/kg
93 kN·m/kg

Specific Stiffness (E / density)

15.1 MN·m/kg
14.6 MN·m/kg

Modulus of Resilience

455 kJ/m³
1,044 kJ/m³

Thermal Diffusivity

7 mm²/s
9.2 mm²/s

Thermal Shock Resistance Index

10
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 704CZr 705

Manufacturing and finishing

CapabilityZr 704CZr 705
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

Zr 704C vs Zr 705 — frequently asked

Is Zr 705 stronger than Zr 704C?

Yes. Zr 705 has a typical yield strength of 450 MPa (65.3 ksi) against 300 MPa (43.5 ksi) for Zr 704C — about 50% more. Tensile strength is 620 MPa (89.9 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, Zr 704C 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 is easier to machine, Zr 704C or Zr 705?

Zr 705. Its machinability rates fair (35/100) against poor (30/100) for Zr 704C.

Ready to make it?

Upload a CAD file and FabDigit prices the part in Zr 704C 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.