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KNN vs PZT-4

Ceramic · grade comparison

KNN and PZT-4 are both ceramic grades. KNN is harder — 400 HV against 320 HV for PZT-4 — which matters for wear surfaces and threads. KNN is lighter (4.5 g/cm³ vs 7.5 g/cm³ for PZT-4) and KNN is stiffer (105 GPa vs 70 GPa).

KNNChoose it when surface hardness matters, or when weight is the constraint.

KNN vs PZT-4: properties

KNNPZT-4

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

105 GPa15.2 Msi
70 GPa10.2 Msi

Shear Modulus

40 GPa5.8 Msi
26 GPa3.8 Msi

Bulk Modulus

88 GPa12.8 Msi
60 GPa8.7 Msi

Poisson's Ratio

0.3
0.31

Compressive Strength

550 MPa79.8 ksi
520 MPa75.4 ksi

Flexural Strength

100 MPa14.5 ksi
85 MPa12.3 ksi

Hardness, Vickers

400 HV
320 HV

Hardness, Mohs

5.5
5

Tensile Strength (Ultimate)

—
75 MPa10.9 ksi

Elongation at Break

—
0.1%

Shear Strength

—
65 MPa9.4 ksi

Hardness, Knoop

—
300 HK

Same in both: Fracture Toughness (K_IC) 1 MPa·√m0.91 ksi·√in

Physical

Density and transition temperatures.

Density

4.5 g/cm³0.16 lb/in³
7.5 g/cm³0.27 lb/in³

Melting Point (Solidus)

1,140°C2,084 °F
—

Refractive Index

2.2
—

Porosity

1.5%
1%

Thermal

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

Thermal Conductivity

2.5 W/m·K1.4 BTU/hr·ft·°F
1.3 W/m·K0.72 BTU/hr·ft·°F

Specific Heat Capacity

420 J/kg·K0.1 BTU/lb·°F
350 J/kg·K0.08 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

7 µm/m·K3.9 µin/in·°F
4 µm/m·K2.2 µin/in·°F

Max Service Temperature (continuous)

150°C302 °F
160°C320 °F

Same in both: Min Service Temperature -50°C-58 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10⁹ Ω·m3.94×10¹⁶ µΩ·in
1×10¹¹ Ω·m3.94×10¹⁸ µΩ·in

Dielectric Strength

6 kV/mm152 V/mil
10 kV/mm254 V/mil

Dielectric Constant (1 MHz)

1,050
1,300

Dissipation Factor (1 MHz)

0.03
0.004

Volume Resistivity

1×10¹¹ Ω·cm
1×10¹³ Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

62 / 100
65 / 100

Manufacturability

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

Machinability

8 / 100
12 / 100

Sintering / Firing Temperature

1,110°C2,030 °F
1,275°C2,327 °F

Same in both: Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

160 MJ/kg68,788 BTU/lb
—

Embodied Carbon (primary production)

11 kg CO₂/kg
—

Embodied Water

250 L/kg30 gal/lb
—

Typical Recycled Content

0%
—

Common Calculations

Ratios derived from the values above.

Specific Stiffness (E / density)

23.3 MN·m/kg
9.3 MN·m/kg

Thermal Diffusivity

1.3 mm²/s
0.5 mm²/s

Strength versus weight

Yield strength against density for every ceramic grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

501002005001,000234567Density (g/cm³)Yield strength (MPa) — log scale

Manufacturing and finishing

CapabilityKNNPZT-4
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

KNN vs PZT-4 — frequently asked

What is the difference between KNN and PZT-4?

KNN and PZT-4 are both ceramic grades. KNN is harder — 400 HV against 320 HV for PZT-4 — which matters for wear surfaces and threads. KNN is lighter (4.5 g/cm³ vs 7.5 g/cm³ for PZT-4) and KNN is stiffer (105 GPa vs 70 GPa).

Which is cheaper, KNN or PZT-4?

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.

When should I choose KNN over PZT-4?

Pick KNN when surface hardness matters, or when weight is the constraint.

Ready to make it?

Upload a CAD file and FabDigit prices the part in KNN and PZT-4 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.