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FEP vs PTFE-Bronze40

Polymer · grade comparison

FEP and PTFE-Bronze40 are both polymer grades. FEP is the stronger of the two: yield strength 13 MPa (1.89 ksi) against 11 MPa (1.6 ksi) for PTFE-Bronze40, about 18% more; tensile strength follows at 23 MPa (3.34 ksi) vs 16 MPa (2.32 ksi). FEP is the more ductile: elongation 320% versus 150% for PTFE-Bronze40, and PTFE-Bronze40 is harder (65 Shore D vs 56 Shore D). FEP is lighter (2.15 g/cm³ vs 3.1 g/cm³ for PTFE-Bronze40) and PTFE-Bronze40 is stiffer (1.1 GPa vs 0.48 GPa). On the shop floor, PTFE-Bronze40 machines more easily (very good vs good), FEP welds better (very good vs not recommended), and PTFE-Bronze40 sits in a lower cost tier (high, $$$$) than FEP (specialty, $$$$$).

FEPChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.

PTFE-Bronze40Choose it when the part sees heat, or when the part is machined in volume.

FEP vs PTFE-Bronze40: properties

FEPPTFE-Bronze40

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

0.48 GPa0.07 Msi
1.1 GPa0.16 Msi

Shear Modulus

0.18 GPa0.03 Msi
—

Poisson's Ratio

0.45
0.42

Tensile Strength (Ultimate)

23 MPa3.3 ksi
16 MPa2.3 ksi

Yield Strength (0.2% offset)

13 MPa1.9 ksi
11 MPa1.6 ksi

Elongation at Break

320%
150%

Compressive Strength

16 MPa2.3 ksi
22 MPa3.2 ksi

Flexural Modulus

0.6 GPa0.09 Msi
1.2 GPa0.17 Msi

Izod Impact, Notched

2,700 J/m50.6 ft·lbf/in
70 J/m1.3 ft·lbf/in

Hardness, Shore D

56 Shore D
65 Shore D

Hardness, Rockwell R

25 HRR
70 HRR

Compressive Modulus

—
1.2 GPa0.17 Msi

Flexural Strength

—
16 MPa2.3 ksi

Shear Strength

—
14 MPa2 ksi

Fracture Toughness (K_IC)

—
2 MPa·√m1.8 ksi·√in

Hardness, Shore A

—
98 Shore A

Physical

Density and transition temperatures.

Density

2.15 g/cm³0.08 lb/in³
3.1 g/cm³0.11 lb/in³

Melting Temperature (Tm)

260°C500 °F
327°C621 °F

Glass Transition (Tg)

-90°C-130 °F
-97°C-143 °F

Water Absorption (24 h)

0.01%
0.04%

Water Absorption (Saturation)

0.01%
—

Refractive Index

1.344
—

Light Transmission

95%
—

Thermal

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

Thermal Conductivity

0.2 W/m·K0.12 BTU/hr·ft·°F
0.45 W/m·K0.26 BTU/hr·ft·°F

Specific Heat Capacity

1,170 J/kg·K0.28 BTU/lb·°F
760 J/kg·K0.18 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

100 µm/m·K55.6 µin/in·°F
90 µm/m·K50 µin/in·°F

Max Service Temperature (continuous)

200°C392 °F
250°C482 °F

Min Service Temperature

-200°C-328 °F
-190°C-310 °F

Heat Deflection Temp. @ 0.45 MPa

70°C158 °F
145°C293 °F

Heat Deflection Temp. @ 1.8 MPa

51°C124 °F
80°C176 °F

Max Service Temperature (short-term)

230°C446 °F
300°C572 °F

Same in both: Limiting Oxygen Index 95%

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹⁶ Ω·m3.94×10²³ µΩ·in
10,000 Ω·m3.94×10¹¹ µΩ·in

Dielectric Strength

24 kV/mm610 V/mil
—

Dielectric Constant (1 MHz)

2.1
—

Dissipation Factor (1 MHz)

6×10⁻⁴
—

Volume Resistivity

1×10¹⁸ Ω·cm
1,000,000 Ω·cm

Surface Resistivity

1×10¹⁶ Ω
—

Comparative Tracking Index (CTI)

600 V
—

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

98 / 100
70 / 100

UV / Weathering Resistance

98 / 100
95 / 100

Manufacturability

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

Machinability

55 / 100
70 / 100

Weldability

80 / 100
5 / 100

Formability (cold)

75 / 100
15 / 100

Polishability

45 / 100
30 / 100

Mold Shrinkage

4%
2.2%

Melt Flow Rate

7 g/10 min
—

Processing Melt Temperature (typ.)

350°C662 °F
375°C707 °F

Mold Temperature (typ.)

200°C392 °F
—

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

220 MJ/kg94,583 BTU/lb
145 MJ/kg62,339 BTU/lb

Embodied Carbon (primary production)

12 kg CO₂/kg
7 kg CO₂/kg

Embodied Water

300 L/kg35.9 gal/lb
—

Same in both: Typical Recycled Content 0%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

11 kN·m/kg
5 kN·m/kg

Specific Stiffness (E / density)

0.2 MN·m/kg
0.4 MN·m/kg

Modulus of Resilience

176 kJ/m³
55 kJ/m³

Thermal Diffusivity

0.1 mm²/s
0.2 mm²/s

Same in both: Thermal Shock Resistance Index 0

Strength versus weight

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

0.1110100123Density (g/cm³)Yield strength (MPa) — log scaleFEPPTFE-Bronze40

Manufacturing and finishing

CapabilityFEPPTFE-Bronze40
CNC machiningYes—
Sheet metalYes—
Injection moldingYes—
Default conditionUnfilled—
Relative cost$$$$$ Specialty$$$$ High
Min. machined wall0.5 mm—
Best machined surfaceRa 0.8 µm—
Chrome Plating (Plastic)Yes—
EMI Shielding CoatingYes—
PaintingYes—
Soft Touch CoatingYes—
Spray PaintingYes—
UV CoatingYes—

FEP vs PTFE-Bronze40 — frequently asked

Is FEP stronger than PTFE-Bronze40?

Yes. FEP has a typical yield strength of 13 MPa (1.89 ksi) against 11 MPa (1.6 ksi) for PTFE-Bronze40 — about 18% more. Tensile strength is 23 MPa (3.34 ksi) vs 16 MPa (2.32 ksi).

Which is cheaper, FEP or PTFE-Bronze40?

PTFE-Bronze40 is the lower-cost material: it sits in the high tier ($$$$) while FEP is specialty ($$$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, FEP or PTFE-Bronze40?

PTFE-Bronze40. Its machinability rates very good (70/100) against good (55/100) for FEP; for welding the order is FEP first (very good, 80/100) then PTFE-Bronze40 (not recommended, 5/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in FEP and PTFE-Bronze40 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.