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AgBr vs Sapphire

Glass · grade comparison

AgBr and Sapphire are both glass grades. Sapphire is the stronger of the two: tensile strength 400 MPa (58 ksi) against 20 MPa (2.9 ksi) for AgBr, about 20 times as much. In exchange, AgBr is the more ductile: elongation 40% versus 0% for Sapphire, and Sapphire is harder (2,000 HV vs 8 HV). Sapphire is lighter (3.98 g/cm³ vs 6.47 g/cm³ for AgBr) and Sapphire is stiffer (400 GPa vs 22 GPa). On the shop floor, AgBr machines more easily (poor vs not recommended) and Sapphire sits in a lower cost tier (standard, $$) than AgBr (high, $$$$).

AgBrChoose 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.

AgBr vs Sapphire: properties

AgBrSapphire

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

22 GPa3.2 Msi
400 GPa58 Msi

Shear Modulus

8 GPa1.2 Msi
148 GPa21.5 Msi

Bulk Modulus

40 GPa5.8 Msi
250 GPa36.3 Msi

Poisson's Ratio

0.4
0.27

Tensile Strength (Ultimate)

20 MPa2.9 ksi
400 MPa58 ksi

Elongation at Break

40%
0%

Compressive Strength

45 MPa6.5 ksi
2,000 MPa290 ksi

Flexural Strength

22 MPa3.2 ksi
760 MPa110 ksi

Hardness, Vickers

8 HV
2,000 HV

Hardness, Knoop

7 HK
2,000 HK

Hardness, Mohs

1.8
9

Shear Strength

—
350 MPa50.8 ksi

Fracture Toughness (K_IC)

—
2.2 MPa·√m2 ksi·√in

Physical

Density and transition temperatures.

Density

6.47 g/cm³0.23 lb/in³
3.98 g/cm³0.14 lb/in³

Melting Point (Solidus)

432°C810 °F
2,053°C3,727 °F

Refractive Index

2.25
1.768

Light Transmission

76%
85%

Same in both: Porosity 0%

Thermal

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

Thermal Conductivity

1.1 W/m·K0.64 BTU/hr·ft·°F
27 W/m·K15.6 BTU/hr·ft·°F

Specific Heat Capacity

280 J/kg·K0.07 BTU/lb·°F
761 J/kg·K0.18 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

33 µm/m·K18.3 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

-180°C-292 °F
-269°C-452 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1,000,000 Ω·m3.94×10¹³ µΩ·in
1×10¹⁴ Ω·m3.94×10²¹ µΩ·in

Dielectric Constant (1 MHz)

12.5
9.8

Volume Resistivity

1×10⁸ 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

72 / 100
95 / 100

Manufacturability

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

Machinability

30 / 100
5 / 100

Polishability

55 / 100
98 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

900 MJ/kg386,931 BTU/lb
400 MJ/kg171,969 BTU/lb

Embodied Carbon (primary production)

70 kg CO₂/kg
60 kg CO₂/kg

Embodied Water

400 L/kg47.9 gal/lb
250 L/kg30 gal/lb

Typical Recycled Content

40%
5%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

3 kN·m/kg
101 kN·m/kg

Specific Stiffness (E / density)

3.4 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

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

AgBr vs Sapphire — frequently asked

Is Sapphire stronger than AgBr?

Yes. Sapphire has a typical tensile strength of 400 MPa (58 ksi) against 20 MPa (2.9 ksi) for AgBr — about 20 times as much.

Which is cheaper, AgBr or Sapphire?

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

AgBr. 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 AgBr 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.