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Refractory Metal M5 vs Zr 704C

Refractory Metal · grade comparison

Refractory Metal M5 and Zr 704C are both refractory metal grades. M5 is the stronger of the two: yield strength 330 MPa (47.9 ksi) against 300 MPa (43.5 ksi) for Zr 704C, about 10% more. M5 is the more ductile: elongation 30% versus 13% for Zr 704C, and Zr 704C is harder (190 HB vs 165 HB). M5 conducts heat better (17.5 W/m·K vs 13 W/m·K).

M5Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

M5 vs Zr 704C: properties

M5Zr 704C

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Bulk Modulus

100 GPa14.5 Msi
97 GPa14.1 Msi

Poisson's Ratio

0.35
0.34

Tensile Strength (Ultimate)

470 MPa68.2 ksi
450 MPa65.3 ksi

Yield Strength (0.2% offset)

330 MPa47.9 ksi
300 MPa43.5 ksi

Elongation at Break

30%
13%

Reduction in Area

55%
20%

Compressive Strength

340 MPa49.3 ksi
320 MPa46.4 ksi

Shear Strength

290 MPa42.1 ksi
300 MPa43.5 ksi

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
20 J14.8 ft·lbf

Hardness, Brinell

165 HB
190 HB

Hardness, Rockwell B

88 HRB
89 HRB

Hardness, Vickers

175 HV
200 HV

Same in both: Elastic (Young's) Modulus 99 GPa14.4 Msi · Shear Modulus 36 GPa5.2 Msi · Fatigue Strength (Endurance Limit) 200 MPa29 ksi · Fracture Toughness (K_IC) 50 MPa·√m45.5 ksi·√in

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,840°C3,344 °F
1,800°C3,272 °F

Liquidus Temperature

1,860°C3,380 °F
1,845°C3,353 °F

Thermal

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

Thermal Conductivity

17.5 W/m·K10.1 BTU/hr·ft·°F
13 W/m·K7.5 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

5.8 µm/m·K3.2 µin/in·°F
6 µm/m·K3.3 µin/in·°F

Latent Heat of Fusion

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

Min Service Temperature

-196°C-321 °F
-75°C-103 °F

Same in both: Specific Heat Capacity 285 J/kg·K0.07 BTU/lb·°F · Max Service Temperature (continuous) 400°C752 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

3.1 % IACS
2.5 % IACS

Electrical Resistivity

5.5×10⁻⁷ Ω·m21.7 µΩ·in
6.8×10⁻⁷ Ω·m26.8 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.3 V
-0.15 V

Same in both: Corrosion Resistance 90 / 100

Manufacturability

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

Machinability Rating (AISI 1212 = 100 %)

25%
28%

Weldability

70 / 100
65 / 100

Formability (cold)

65 / 100
20 / 100

Castability

25 / 100
55 / 100

Brazeability / Solderability

30 / 100
20 / 100

Polishability

70 / 100
60 / 100

Same in both: Machinability 30 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

1,250 MJ/kg537,404 BTU/lb
1,200 MJ/kg515,908 BTU/lb

Embodied Carbon (primary production)

80 kg CO₂/kg
75 kg CO₂/kg

Embodied Water

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

Typical Recycled Content

15%
25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

72 kN·m/kg
69 kN·m/kg

Modulus of Resilience

550 kJ/m³
455 kJ/m³

Thermal Diffusivity

9.4 mm²/s
7 mm²/s

Thermal Shock Resistance Index

14
10

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.

1502003005007001,0001,5005101520Density (g/cm³)Yield strength (MPa) — log scaleZr 704CM5

Manufacturing and finishing

CapabilityM5Zr 704C
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

M5 vs Zr 704C — frequently asked

Is M5 stronger than Zr 704C?

Yes. M5 has a typical yield strength of 330 MPa (47.9 ksi) against 300 MPa (43.5 ksi) for Zr 704C — about 10% more. Tensile strength is 470 MPa (68.2 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, M5 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.

Which welds better, M5 or Zr 704C?

M5. Its weldability rates very good (70/100) against good (65/100) for Zr 704C.

Ready to make it?

Upload a CAD file and FabDigit prices the part in M5 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.