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N-K5 vs N-LaK9

Glass · grade comparison

N-K5 and N-LaK9 are both glass grades. N-LaK9 is the stronger of the two: tensile strength 55 MPa (7.98 ksi) against 40 MPa (5.8 ksi) for N-K5, about 38% more. N-LaK9 is harder — 640 HV against 520 HV for N-K5 — which matters for wear surfaces and threads. N-K5 is lighter (2.59 g/cm³ vs 3.51 g/cm³ for N-LaK9) and N-LaK9 is stiffer (110 GPa vs 71 GPa). On the shop floor, N-K5 machines more easily (fair vs not recommended).

N-K5Choose it when weight is the constraint, or when the part is machined in volume.

N-LaK9Choose it when strength drives the design, or when surface hardness matters.

N-K5 vs N-LaK9: properties

N-K5N-LaK9

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

71 GPa10.3 Msi
110 GPa16 Msi

Shear Modulus

29 GPa4.2 Msi
42.7 GPa6.2 Msi

Bulk Modulus

43 GPa6.2 Msi
86 GPa12.5 Msi

Poisson's Ratio

0.22
0.29

Tensile Strength (Ultimate)

40 MPa5.8 ksi
55 MPa8 ksi

Compressive Strength

900 MPa131 ksi
1,000 MPa145 ksi

Flexural Strength

65 MPa9.4 ksi
70 MPa10.2 ksi

Hardness, Vickers

520 HV
640 HV

Hardness, Knoop

530 HK
680 HK

Same in both: Fracture Toughness (K_IC) 0.8 MPa·√m0.73 ksi·√in · Hardness, Mohs 6

Physical

Density and transition temperatures.

Density

2.59 g/cm³0.09 lb/in³
3.51 g/cm³0.13 lb/in³

Refractive Index

1.523
1.691

Light Transmission

92%
100%

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
0.9 W/m·K0.52 BTU/hr·ft·°F

Specific Heat Capacity

783 J/kg·K0.19 BTU/lb·°F
510 J/kg·K0.12 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

8.2 µm/m·K4.6 µin/in·°F
6.3 µm/m·K3.5 µin/in·°F

Max Service Temperature (continuous)

400°C752 °F
500°C932 °F

Same in both: Min Service Temperature -60°C-76 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹² Ω·m3.94×10¹⁹ µΩ·in
—

Dielectric Strength

12 kV/mm305 V/mil
—

Dielectric Constant (1 MHz)

7
8.5

Dissipation Factor (1 MHz)

0.008
—

Same in both: Volume Resistivity 1×10¹⁴ Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

70 / 100
62 / 100

Manufacturability

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

Machinability

35 / 100
12 / 100

Polishability

88 / 100
85 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

42 MJ/kg18,057 BTU/lb
60 MJ/kg25,795 BTU/lb

Embodied Carbon (primary production)

2.6 kg CO₂/kg
4.5 kg CO₂/kg

Embodied Water

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

Typical Recycled Content

5%
20%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

15 kN·m/kg
16 kN·m/kg

Specific Stiffness (E / density)

27.4 MN·m/kg
31.3 MN·m/kg

Same in both: Thermal Diffusivity 0.5 mm²/s · 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-K5N-LaK9
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

N-K5 vs N-LaK9 — frequently asked

Is N-LaK9 stronger than N-K5?

Yes. N-LaK9 has a typical tensile strength of 55 MPa (7.98 ksi) against 40 MPa (5.8 ksi) for N-K5 — about 38% more.

Which is cheaper, N-K5 or N-LaK9?

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 N-LaK9?

N-K5. Its machinability rates fair (35/100) against not recommended (12/100) for N-LaK9.

Ready to make it?

Upload a CAD file and FabDigit prices the part in N-K5 and N-LaK9 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.