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NaCl vs Sapphire

Glass · grade comparison

NaCl and Sapphire are both glass grades. Sapphire is the stronger of the two: tensile strength 400 MPa (58 ksi) against 3 MPa (0.435 ksi) for NaCl, about 133 times as much. Sapphire is harder — 2,000 HV against 20 HV for NaCl — which matters for wear surfaces and threads. NaCl is lighter (2.17 g/cm³ vs 3.98 g/cm³ for Sapphire) and Sapphire is stiffer (400 GPa vs 40 GPa). On the shop floor, NaCl machines more easily (fair vs not recommended) and Sapphire sits in a lower cost tier (standard, $$) than NaCl (high, $$$$).

NaClChoose it when weight is the constraint, or when the part is machined in volume.

SapphireChoose it when strength drives the design, or when surface hardness matters.

NaCl vs Sapphire: properties

NaClSapphire

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

40 GPa5.8 Msi
400 GPa58 Msi

Shear Modulus

14.9 GPa2.2 Msi
148 GPa21.5 Msi

Bulk Modulus

24 GPa3.5 Msi
250 GPa36.3 Msi

Poisson's Ratio

0.25
0.27

Tensile Strength (Ultimate)

3 MPa0.44 ksi
400 MPa58 ksi

Compressive Strength

25 MPa3.6 ksi
2,000 MPa290 ksi

Flexural Strength

2 MPa0.35 ksi
760 MPa110 ksi

Shear Strength

2 MPa0.29 ksi
350 MPa50.8 ksi

Fracture Toughness (K_IC)

0.3 MPa·√m0.27 ksi·√in
2.2 MPa·√m2 ksi·√in

Hardness, Vickers

20 HV
2,000 HV

Hardness, Knoop

18 HK
2,000 HK

Hardness, Mohs

2.5
9

Elongation at Break

—
0%

Physical

Density and transition temperatures.

Density

2.17 g/cm³0.08 lb/in³
3.98 g/cm³0.14 lb/in³

Melting Point (Solidus)

801°C1,474 °F
2,053°C3,727 °F

Refractive Index

1.544
1.768

Light Transmission

90%
85%

Same in both: Porosity 0%

Thermal

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

Thermal Conductivity

6.5 W/m·K3.8 BTU/hr·ft·°F
27 W/m·K15.6 BTU/hr·ft·°F

Specific Heat Capacity

854 J/kg·K0.2 BTU/lb·°F
761 J/kg·K0.18 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

44 µm/m·K24.4 µin/in·°F
5.8 µm/m·K3.2 µin/in·°F

Max Service Temperature (continuous)

400°C752 °F
1,800°C3,272 °F

Min Service Temperature

-190°C-310 °F
-269°C-452 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹² Ω·m3.94×10¹⁹ µΩ·in
1×10¹⁴ Ω·m3.94×10²¹ µΩ·in

Dielectric Strength

15 kV/mm381 V/mil
17 kV/mm432 V/mil

Dielectric Constant (1 MHz)

5.9
9.8

Dissipation Factor (1 MHz)

5×10⁻⁴
1×10⁻⁴

Volume Resistivity

1×10¹⁴ Ω·cm
1×10¹⁶ Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

5 / 100
95 / 100

Manufacturability

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

Machinability

45 / 100
5 / 100

Polishability

50 / 100
98 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

20 MJ/kg8,598 BTU/lb
400 MJ/kg171,969 BTU/lb

Embodied Carbon (primary production)

1.2 kg CO₂/kg
60 kg CO₂/kg

Embodied Water

20 L/kg2.4 gal/lb
250 L/kg30 gal/lb

Typical Recycled Content

20%
5%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

1 kN·m/kg
101 kN·m/kg

Specific Stiffness (E / density)

18.5 MN·m/kg
100.5 MN·m/kg

Thermal Diffusivity

3.5 mm²/s
8.9 mm²/s

Thermal Shock Resistance Index

0
5

Strength versus weight

Yield strength against density for every glass grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

501002005002.533.5Density (g/cm³)Yield strength (MPa) — log scaleSapphire

Manufacturing and finishing

CapabilityNaClSapphire
Default condition—Annealed Glass
Relative cost$$$$ High$$ Standard
Min. machined wall——
Best machined surface——

NaCl vs Sapphire — frequently asked

Is Sapphire stronger than NaCl?

Yes. Sapphire has a typical tensile strength of 400 MPa (58 ksi) against 3 MPa (0.435 ksi) for NaCl — about 133 times as much.

Which is cheaper, NaCl or Sapphire?

Sapphire is the lower-cost material: it sits in the standard tier ($$) while NaCl is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, NaCl or Sapphire?

NaCl. Its machinability rates fair (45/100) against not recommended (5/100) for Sapphire.

Ready to make it?

Upload a CAD file and FabDigit prices the part in NaCl and Sapphire 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.