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N-K5 vs SF11

Glass · grade comparison

N-K5 and SF11 are both glass grades. N-K5 is harder — 520 HV against 450 HV for SF11 — which matters for wear surfaces and threads. N-K5 is lighter (2.59 g/cm³ vs 4.74 g/cm³ for SF11) and N-K5 is stiffer (71 GPa vs 66 GPa). On the shop floor, N-K5 machines more easily (fair vs poor).

N-K5Choose it when surface hardness matters, or when weight is the constraint.

N-K5 vs SF11: properties

N-K5SF11

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

71 GPa10.3 Msi
66 GPa9.6 Msi

Shear Modulus

29 GPa4.2 Msi
26.7 GPa3.9 Msi

Bulk Modulus

43 GPa6.2 Msi
42 GPa6 Msi

Poisson's Ratio

0.22
0.24

Compressive Strength

900 MPa131 ksi
800 MPa116 ksi

Flexural Strength

65 MPa9.4 ksi
55 MPa8 ksi

Fracture Toughness (K_IC)

0.8 MPa·√m0.73 ksi·√in
0.65 MPa·√m0.59 ksi·√in

Hardness, Vickers

520 HV
450 HV

Hardness, Knoop

530 HK
450 HK

Hardness, Mohs

6
5

Elongation at Break

—
0%

Same in both: Tensile Strength (Ultimate) 40 MPa5.8 ksi

Physical

Density and transition temperatures.

Density

2.59 g/cm³0.09 lb/in³
4.74 g/cm³0.17 lb/in³

Refractive Index

1.523
1.785

Light Transmission

92%
85%

Same in both: Porosity 0%

Thermal

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

Thermal Conductivity

1.1 W/m·K0.62 BTU/hr·ft·°F
0.74 W/m·K0.43 BTU/hr·ft·°F

Specific Heat Capacity

783 J/kg·K0.19 BTU/lb·°F
431 J/kg·K0.1 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

8.2 µm/m·K4.6 µin/in·°F
6.1 µm/m·K3.4 µin/in·°F

Min Service Temperature

-60°C-76 °F
-200°C-328 °F

Same in both: Max Service Temperature (continuous) 400°C752 °F

Electrical

Conductivity and insulation.

Dielectric Strength

12 kV/mm305 V/mil
15 kV/mm381 V/mil

Dielectric Constant (1 MHz)

7
8.5

Dissipation Factor (1 MHz)

0.008
0.001

Same in both: Electrical Resistivity 1×10¹² Ω·m3.94×10¹⁹ µΩ·in · Volume Resistivity 1×10¹⁴ Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

70 / 100
45 / 100

Manufacturability

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

Machinability

35 / 100
25 / 100

Polishability

88 / 100
95 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

42 MJ/kg18,057 BTU/lb
45 MJ/kg19,347 BTU/lb

Embodied Carbon (primary production)

2.6 kg CO₂/kg
3.2 kg CO₂/kg

Embodied Water

25 L/kg3 gal/lb
120 L/kg14.4 gal/lb

Same in both: Typical Recycled Content 5%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

15 kN·m/kg
8 kN·m/kg

Specific Stiffness (E / density)

27.4 MN·m/kg
13.9 MN·m/kg

Thermal Diffusivity

0.5 mm²/s
0.4 mm²/s

Same in both: Thermal Shock Resistance Index 0

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

CapabilityN-K5SF11
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

N-K5 vs SF11 — frequently asked

What is the difference between N-K5 and SF11?

N-K5 and SF11 are both glass grades. N-K5 is harder — 520 HV against 450 HV for SF11 — which matters for wear surfaces and threads. N-K5 is lighter (2.59 g/cm³ vs 4.74 g/cm³ for SF11) and N-K5 is stiffer (71 GPa vs 66 GPa).

Which is cheaper, N-K5 or SF11?

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, N-K5 or SF11?

N-K5. Its machinability rates fair (35/100) against poor (25/100) for SF11.

Ready to make it?

Upload a CAD file and FabDigit prices the part in N-K5 and SF11 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.