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AgCl vs Sapphire

Glass · grade comparison

AgCl and Sapphire are both glass grades. Sapphire is the stronger of the two: tensile strength 400 MPa (58 ksi) against 26 MPa (3.77 ksi) for AgCl, about 15 times as much. In exchange, AgCl is the more ductile: elongation 20% versus 0% for Sapphire, and Sapphire is harder (2,000 HV vs 10 HV). Sapphire is lighter (3.98 g/cm³ vs 5.56 g/cm³ for AgCl) and Sapphire is stiffer (400 GPa vs 20 GPa). On the shop floor, AgCl machines more easily (poor vs not recommended) and Sapphire sits in a lower cost tier (standard, $$) than AgCl (high, $$$$).

AgClChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

SapphireChoose it when strength drives the design, or when weight is the constraint.

AgCl vs Sapphire: properties

AgClSapphire

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

20 GPa2.9 Msi
400 GPa58 Msi

Shear Modulus

7 GPa1 Msi
148 GPa21.5 Msi

Bulk Modulus

44 GPa6.4 Msi
250 GPa36.3 Msi

Poisson's Ratio

0.4
0.27

Tensile Strength (Ultimate)

26 MPa3.8 ksi
400 MPa58 ksi

Elongation at Break

20%
0%

Compressive Strength

55 MPa8 ksi
2,000 MPa290 ksi

Flexural Strength

20 MPa2.9 ksi
760 MPa110 ksi

Shear Strength

15 MPa2.2 ksi
350 MPa50.8 ksi

Fracture Toughness (K_IC)

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

Hardness, Vickers

10 HV
2,000 HV

Hardness, Knoop

10 HK
2,000 HK

Hardness, Mohs

2
9

Physical

Density and transition temperatures.

Density

5.56 g/cm³0.2 lb/in³
3.98 g/cm³0.14 lb/in³

Melting Point (Solidus)

455°C851 °F
2,053°C3,727 °F

Refractive Index

2
1.768

Light Transmission

80%
85%

Same in both: Porosity 0%

Thermal

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

Thermal Conductivity

1.2 W/m·K0.66 BTU/hr·ft·°F
27 W/m·K15.6 BTU/hr·ft·°F

Specific Heat Capacity

354 J/kg·K0.08 BTU/lb·°F
761 J/kg·K0.18 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

30 µm/m·K16.7 µin/in·°F
5.8 µm/m·K3.2 µin/in·°F

Max Service Temperature (continuous)

200°C392 °F
1,800°C3,272 °F

Min Service Temperature

-190°C-310 °F
-269°C-452 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10⁹ Ω·m3.94×10¹⁶ µΩ·in
1×10¹⁴ Ω·m3.94×10²¹ µΩ·in

Dielectric Constant (1 MHz)

11.1
9.8

Volume Resistivity

1×10¹¹ Ω·cm
1×10¹⁶ Ω·cm

Dielectric Strength

—
17 kV/mm432 V/mil

Dissipation Factor (1 MHz)

—
1×10⁻⁴

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

70 / 100
95 / 100

Manufacturability

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

Machinability

30 / 100
5 / 100

Polishability

40 / 100
98 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

1,200 MJ/kg515,908 BTU/lb
400 MJ/kg171,969 BTU/lb

Embodied Carbon (primary production)

80 kg CO₂/kg
60 kg CO₂/kg

Embodied Water

1,500 L/kg180 gal/lb
250 L/kg30 gal/lb

Typical Recycled Content

40%
5%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

5 kN·m/kg
101 kN·m/kg

Specific Stiffness (E / density)

3.6 MN·m/kg
100.5 MN·m/kg

Thermal Diffusivity

0.6 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

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

AgCl vs Sapphire — frequently asked

Is Sapphire stronger than AgCl?

Yes. Sapphire has a typical tensile strength of 400 MPa (58 ksi) against 26 MPa (3.77 ksi) for AgCl — about 15 times as much.

Which is cheaper, AgCl or Sapphire?

Sapphire is the lower-cost material: it sits in the standard tier ($$) while AgCl is high ($$$$). 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, AgCl or Sapphire?

AgCl. Its machinability rates poor (30/100) against not recommended (5/100) for Sapphire.

Ready to make it?

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