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CaF2 vs GaAs

Glass · grade comparison

CaF2 and GaAs are both glass grades. GaAs is the stronger of the two: tensile strength 70 MPa (10.2 ksi) against 37 MPa (5.37 ksi) for CaF2, about 89% more. GaAs is harder — 600 HV against 165 HV for CaF2 — which matters for wear surfaces and threads. CaF2 is lighter (3.18 g/cm³ vs 5.32 g/cm³ for GaAs) and GaAs is stiffer (85.5 GPa vs 75.8 GPa). On the shop floor, CaF2 machines more easily (45 vs 35 out of 100).

CaF2Choose it when weight is the constraint, or when the part sees heat.

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

CaF2 vs GaAs: properties

CaF2GaAs

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

75.8 GPa11 Msi
85.5 GPa12.4 Msi

Shear Modulus

33.8 GPa4.9 Msi
32.9 GPa4.8 Msi

Bulk Modulus

83 GPa12 Msi
76 GPa11 Msi

Poisson's Ratio

0.26
0.31

Tensile Strength (Ultimate)

37 MPa5.4 ksi
70 MPa10.2 ksi

Flexural Strength

37 MPa5.4 ksi
90 MPa13.1 ksi

Fracture Toughness (K_IC)

0.33 MPa·√m0.3 ksi·√in
0.44 MPa·√m0.4 ksi·√in

Hardness, Vickers

165 HV
600 HV

Hardness, Knoop

158 HK
731 HK

Hardness, Mohs

4
4.5

Elongation at Break

—
0%

Compressive Strength

—
700 MPa102 ksi

Shear Strength

—
55 MPa8 ksi

Physical

Density and transition temperatures.

Density

3.18 g/cm³0.11 lb/in³
5.32 g/cm³0.19 lb/in³

Melting Point (Solidus)

1,418°C2,584 °F
1,238°C2,260 °F

Refractive Index

1.434
3.28

Light Transmission

94%
54%

Same in both: Porosity 0%

Thermal

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

Thermal Conductivity

9.7 W/m·K5.6 BTU/hr·ft·°F
55 W/m·K31.8 BTU/hr·ft·°F

Specific Heat Capacity

854 J/kg·K0.2 BTU/lb·°F
327 J/kg·K0.08 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

18.9 µm/m·K10.5 µin/in·°F
5.7 µm/m·K3.2 µin/in·°F

Max Service Temperature (continuous)

800°C1,472 °F
460°C860 °F

Min Service Temperature

-200°C-328 °F
-269°C-452 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

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

Dielectric Constant (1 MHz)

6.76
12.9

Volume Resistivity

1×10¹⁶ Ω·cm
1×10⁸ Ω·cm

Dielectric Strength

—
40 kV/mm1,016 V/mil

Dissipation Factor (1 MHz)

—
6×10⁻⁴

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

45 / 100
55 / 100

Manufacturability

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

Machinability

45 / 100
35 / 100

Polishability

60 / 100
92 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

—
2,000 MJ/kg859,846 BTU/lb

Embodied Carbon (primary production)

—
130 kg CO₂/kg

Embodied Water

—
900 L/kg108 gal/lb

Typical Recycled Content

—
5%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

12 kN·m/kg
13 kN·m/kg

Specific Stiffness (E / density)

23.8 MN·m/kg
16.1 MN·m/kg

Thermal Diffusivity

3.6 mm²/s
31.6 mm²/s

Thermal Shock Resistance Index

0
8

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 scale

Manufacturing and finishing

CapabilityCaF2GaAs
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

CaF2 vs GaAs — frequently asked

Is GaAs stronger than CaF2?

Yes. GaAs has a typical tensile strength of 70 MPa (10.2 ksi) against 37 MPa (5.37 ksi) for CaF2 — about 89% more.

Which is cheaper, CaF2 or GaAs?

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, CaF2 or GaAs?

CaF2, by a small margin. Both rate fair for machinability — 45/100 against 35/100 for GaAs.

Ready to make it?

Upload a CAD file and FabDigit prices the part in CaF2 and GaAs 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.