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PC-FR vs PC/PET

Polymer · grade comparison

PC-FR and PC/PET are both polymer grades. PC-FR is the stronger of the two: yield strength 62 MPa (8.99 ksi) against 53 MPa (7.69 ksi) for PC/PET, about 17% more; tensile strength follows at 64 MPa (9.28 ksi) vs 55 MPa (7.98 ksi). In exchange, PC/PET is the more ductile: elongation 120% versus 100% for PC-FR. PC-FR is stiffer (2.4 GPa vs 2.1 GPa) and PC-FR runs hotter in service (120°C vs 100°C continuous). On the shop floor, PC/PET welds better (very good vs good).

PC-FRChoose it when strength drives the design, or when the part sees heat.

PC/PETChoose it when the part is bent, formed or impact-loaded, or when it will be welded.

PC-FR vs PC/PET: properties

PC-FRPC/PET

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

2.4 GPa0.34 Msi
2.1 GPa0.3 Msi

Shear Modulus

0.85 GPa0.12 Msi
—

Bulk Modulus

4 GPa0.55 Msi
—

Poisson's Ratio

0.39
0.4

Tensile Strength (Ultimate)

64 MPa9.3 ksi
55 MPa8 ksi

Yield Strength (0.2% offset)

62 MPa9 ksi
53 MPa7.7 ksi

Elongation at Break

100%
120%

Compressive Strength

80 MPa11.6 ksi
70 MPa10.2 ksi

Compressive Modulus

2.3 GPa0.33 Msi
—

Flexural Strength

95 MPa13.8 ksi
82 MPa11.9 ksi

Flexural Modulus

2.3 GPa0.33 Msi
2.2 GPa0.32 Msi

Shear Strength

62 MPa9 ksi
—

Fracture Toughness (K_IC)

2.6 MPa·√m2.4 ksi·√in
—

Izod Impact, Notched

650 J/m12.2 ft·lbf/in
700 J/m13.1 ft·lbf/in

Hardness, Shore D

81 Shore D
—

Hardness, Rockwell R

120 HRR
118 HRR

Same in both: Hardness, Rockwell M 72 HRM

Physical

Density and transition temperatures.

Glass Transition (Tg)

147°C297 °F
140°C284 °F

Water Absorption (Saturation)

0.35%
0.4%

Refractive Index

1.586
—

Melting Temperature (Tm)

—
250°C482 °F

Same in both: Density 1.22 g/cm³0.04 lb/in³ · Water Absorption (24 h) 0.15%

Thermal

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

Thermal Conductivity

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

Specific Heat Capacity

1,200 J/kg·K0.29 BTU/lb·°F
1,300 J/kg·K0.31 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

67 µm/m·K37.2 µin/in·°F
70 µm/m·K38.9 µin/in·°F

Max Service Temperature (continuous)

120°C248 °F
100°C212 °F

Heat Deflection Temp. @ 0.45 MPa

140°C284 °F
118°C244 °F

Heat Deflection Temp. @ 1.8 MPa

128°C262 °F
92°C198 °F

Vicat Softening Point (B50)

145°C293 °F
138°C280 °F

Limiting Oxygen Index

34%
26%

Max Service Temperature (short-term)

140°C284 °F
130°C266 °F

Same in both: Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Dielectric Strength

20 kV/mm508 V/mil
22 kV/mm559 V/mil

Dielectric Constant (1 MHz)

2.95
3.1

Dissipation Factor (1 MHz)

0.01
0.012

Surface Resistivity

1×10¹⁵ Ω
1×10¹⁶ Ω

Same in both: Electrical Resistivity 1×10¹⁴ Ω·m3.94×10²¹ µΩ·in · Volume Resistivity 1×10¹⁶ Ω·cm · Comparative Tracking Index (CTI) 250 V

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

60 / 100
—

UV / Weathering Resistance

40 / 100
35 / 100

Manufacturability

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

Machinability

65 / 100
60 / 100

Weldability

60 / 100
70 / 100

Formability (cold)

60 / 100
—

Polishability

75 / 100
55 / 100

Mold Shrinkage

0.6%
0.8%

Melt Flow Rate

10 g/10 min
18 g/10 min

Processing Melt Temperature (typ.)

285°C545 °F
265°C509 °F

Mold Temperature (typ.)

90°C194 °F
75°C167 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

110 MJ/kg47,292 BTU/lb
105 MJ/kg45,142 BTU/lb

Embodied Carbon (primary production)

6.6 kg CO₂/kg
5.5 kg CO₂/kg

Typical Recycled Content

5%
20%

Same in both: Embodied Water 300 L/kg35.9 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

52 kN·m/kg
45 kN·m/kg

Specific Stiffness (E / density)

1.9 MN·m/kg
1.7 MN·m/kg

Modulus of Resilience

818 kJ/m³
669 kJ/m³

Same in both: Thermal Diffusivity 0.1 mm²/s · 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 scalePC-FRPC/PET

Manufacturing and finishing

CapabilityPC-FRPC/PET
3D printingYes—
Default condition——
Relative cost$$$ Premium$$$ Premium
Min. machined wall——
Best machined surface——
Conductive CoatingYes—
Dyeing (Nylon)Yes—
EMI Shielding CoatingYes—
PaintingYes—
Primer CoatingYes—
Soft Touch CoatingYes—
Tinted CoatingYes—
UV CoatingYes—
Vacuum MetallizationYes—
Waterproof CoatingYes—

PC-FR vs PC/PET — frequently asked

Is PC-FR stronger than PC/PET?

Yes. PC-FR has a typical yield strength of 62 MPa (8.99 ksi) against 53 MPa (7.69 ksi) for PC/PET — about 17% more. Tensile strength is 64 MPa (9.28 ksi) vs 55 MPa (7.98 ksi).

Which is cheaper, PC-FR or PC/PET?

Both sit in the same relative cost tier ($$$, premium); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, PC-FR or PC/PET?

PC-FR, by a small margin. Both rate good for machinability — 65/100 against 60/100 for PC/PET; for welding the order is PC/PET first (very good, 70/100) then PC-FR (good, 60/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in PC-FR and PC/PET 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.