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PC-FR vs PC/PBT

Polymer · grade comparison

PC-FR and PC/PBT are both polymer grades. PC-FR is the stronger of the two: yield strength 62 MPa (8.99 ksi) against 52 MPa (7.54 ksi) for PC/PBT, about 19% more; tensile strength follows at 64 MPa (9.28 ksi) vs 53 MPa (7.69 ksi). In exchange, PC/PBT is the more ductile: elongation 120% versus 100% for PC-FR, and PC-FR is harder (81 Shore D vs 76 Shore D). PC-FR is stiffer (2.4 GPa vs 2.2 GPa) and PC-FR runs hotter in service (120°C vs 100°C continuous). On the shop floor, PC/PBT welds better (very good vs good) and PC/PBT sits in a lower cost tier (standard, $$) than PC-FR (premium, $$$).

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

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

PC-FR vs PC/PBT: properties

PC-FRPC/PBT

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

2.4 GPa0.34 Msi
2.2 GPa0.31 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
53 MPa7.7 ksi

Yield Strength (0.2% offset)

62 MPa9 ksi
52 MPa7.5 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
75 MPa10.9 ksi

Flexural Modulus

2.3 GPa0.33 Msi
2.1 GPa0.3 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
750 J/m14 ft·lbf/in

Hardness, Shore D

81 Shore D
76 Shore D

Hardness, Rockwell M

72 HRM
—

Hardness, Rockwell R

120 HRR
115 HRR

Physical

Density and transition temperatures.

Density

1.22 g/cm³0.04 lb/in³
1.21 g/cm³0.04 lb/in³

Glass Transition (Tg)

147°C297 °F
130°C266 °F

Water Absorption (24 h)

0.15%
0.12%

Water Absorption (Saturation)

0.35%
0.4%

Refractive Index

1.586
—

Melting Temperature (Tm)

—
222°C432 °F

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
1,400 J/kg·K0.33 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

67 µm/m·K37.2 µin/in·°F
80 µm/m·K44.4 µin/in·°F

Max Service Temperature (continuous)

120°C248 °F
100°C212 °F

Heat Deflection Temp. @ 0.45 MPa

140°C284 °F
125°C257 °F

Heat Deflection Temp. @ 1.8 MPa

128°C262 °F
95°C203 °F

Vicat Softening Point (B50)

145°C293 °F
135°C275 °F

Limiting Oxygen Index

34%
24%

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.

Electrical Resistivity

1×10¹⁴ Ω·m3.94×10²¹ µΩ·in
1×10¹³ Ω·m3.94×10²⁰ µΩ·in

Dielectric Strength

20 kV/mm508 V/mil
26 kV/mm660 V/mil

Dielectric Constant (1 MHz)

2.95
3.1

Dissipation Factor (1 MHz)

0.01
0.012

Volume Resistivity

1×10¹⁶ Ω·cm
1×10¹⁵ Ω·cm

Comparative Tracking Index (CTI)

250 V
275 V

Same in both: Surface Resistivity 1×10¹⁵ Ω

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

60 / 100
80 / 100

UV / Weathering Resistance

40 / 100
55 / 100

Manufacturability

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

Machinability

65 / 100
62 / 100

Weldability

60 / 100
70 / 100

Formability (cold)

60 / 100
—

Polishability

75 / 100
55 / 100

Mold Shrinkage

0.6%
0.75%

Melt Flow Rate

10 g/10 min
15 g/10 min

Processing Melt Temperature (typ.)

285°C545 °F
260°C500 °F

Mold Temperature (typ.)

90°C194 °F
70°C158 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

110 MJ/kg47,292 BTU/lb
95 MJ/kg40,843 BTU/lb

Embodied Carbon (primary production)

6.6 kg CO₂/kg
5.5 kg CO₂/kg

Embodied Water

300 L/kg35.9 gal/lb
250 L/kg30 gal/lb

Typical Recycled Content

5%
10%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

52 kN·m/kg
44 kN·m/kg

Specific Stiffness (E / density)

1.9 MN·m/kg
1.8 MN·m/kg

Modulus of Resilience

818 kJ/m³
629 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/PBT

Manufacturing and finishing

CapabilityPC-FRPC/PBT
3D printingYes—
Default condition——
Relative cost$$$ Premium$$ Standard
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/PBT — frequently asked

Is PC-FR stronger than PC/PBT?

Yes. PC-FR has a typical yield strength of 62 MPa (8.99 ksi) against 52 MPa (7.54 ksi) for PC/PBT — about 19% more. Tensile strength is 64 MPa (9.28 ksi) vs 53 MPa (7.69 ksi).

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

PC/PBT is the lower-cost material: it sits in the standard tier ($$) while PC-FR is premium ($$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which welds better, PC-FR or PC/PBT?

PC/PBT. Its weldability rates very good (70/100) against good (60/100) for PC-FR.

Ready to make it?

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