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N-K5 vs SF6

Glass · grade comparison

N-K5 and SF6 are both glass grades. N-K5 is harder — 520 HV against 350 HV for SF6 — which matters for wear surfaces and threads. N-K5 is lighter (2.59 g/cm³ vs 5.18 g/cm³ for SF6) and N-K5 is stiffer (71 GPa vs 55 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 SF6: properties

N-K5SF6

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

71 GPa10.3 Msi
55 GPa8 Msi

Shear Modulus

29 GPa4.2 Msi
22 GPa3.2 Msi

Bulk Modulus

43 GPa6.2 Msi
36 GPa5.2 Msi

Poisson's Ratio

0.22
0.24

Flexural Strength

65 MPa9.4 ksi
55 MPa8 ksi

Fracture Toughness (K_IC)

0.8 MPa·√m0.73 ksi·√in
0.6 MPa·√m0.55 ksi·√in

Hardness, Vickers

520 HV
350 HV

Hardness, Knoop

530 HK
310 HK

Hardness, Mohs

6
5

Same in both: Tensile Strength (Ultimate) 40 MPa5.8 ksi · Compressive Strength 900 MPa131 ksi

Physical

Density and transition temperatures.

Density

2.59 g/cm³0.09 lb/in³
5.18 g/cm³0.19 lb/in³

Refractive Index

1.523
1.805

Light Transmission

92%
84%

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
0.67 W/m·K0.39 BTU/hr·ft·°F

Specific Heat Capacity

783 J/kg·K0.19 BTU/lb·°F
389 J/kg·K0.09 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

8.2 µm/m·K4.6 µin/in·°F
8.1 µm/m·K4.5 µin/in·°F

Max Service Temperature (continuous)

400°C752 °F
350°C662 °F

Min Service Temperature

-60°C-76 °F
-100°C-148 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹² Ω·m3.94×10¹⁹ µΩ·in
1×10¹¹ Ω·m3.94×10¹⁸ µΩ·in

Dielectric Strength

12 kV/mm305 V/mil
20 kV/mm508 V/mil

Dielectric Constant (1 MHz)

7
9

Dissipation Factor (1 MHz)

0.008
0.001

Volume Resistivity

1×10¹⁴ Ω·cm
1×10¹³ 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
15 / 100

Same in both: Polishability 88 / 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 kg CO₂/kg

Embodied Water

25 L/kg3 gal/lb
80 L/kg9.6 gal/lb

Typical Recycled Content

5%
10%

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
10.6 MN·m/kg

Thermal Diffusivity

0.5 mm²/s
0.3 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-K5SF6
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

N-K5 vs SF6 — frequently asked

What is the difference between N-K5 and SF6?

N-K5 and SF6 are both glass grades. N-K5 is harder — 520 HV against 350 HV for SF6 — which matters for wear surfaces and threads. N-K5 is lighter (2.59 g/cm³ vs 5.18 g/cm³ for SF6) and N-K5 is stiffer (71 GPa vs 55 GPa).

Which is cheaper, N-K5 or SF6?

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 SF6?

N-K5. Its machinability rates fair (35/100) against poor (15/100) for SF6.

Ready to make it?

Upload a CAD file and FabDigit prices the part in N-K5 and SF6 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.