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MF Moulding Compound vs PBI

Polymer · grade comparison

MF Moulding Compound and PBI are both polymer grades. PBI is the stronger of the two: tensile strength 160 MPa (23.2 ksi) against 62 MPa (8.99 ksi) for MF Moulding Compound, about 158% more. PBI is the more ductile: elongation 3% versus 0.7% for MF Moulding Compound. PBI is lighter (1.3 g/cm³ vs 1.5 g/cm³ for MF Moulding Compound) and MF Moulding Compound is stiffer (8.5 GPa vs 5.9 GPa). On the shop floor, MF Moulding Compound sits in a lower cost tier (standard, $$) than PBI (specialty, $$$$$).

MF Moulding CompoundChoose it when cost is the deciding factor.

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

MF Moulding Compound vs PBI: properties

MF Moulding CompoundPBI

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

8.5 GPa1.2 Msi
5.9 GPa0.86 Msi

Tensile Strength (Ultimate)

62 MPa9 ksi
160 MPa23.2 ksi

Elongation at Break

0.7%
3%

Compressive Strength

240 MPa34.8 ksi
400 MPa58 ksi

Compressive Modulus

9.5 GPa1.4 Msi
5.8 GPa0.84 Msi

Flexural Strength

100 MPa14.5 ksi
220 MPa31.9 ksi

Flexural Modulus

8.3 GPa1.2 Msi
6.5 GPa0.94 Msi

Shear Strength

60 MPa8.7 ksi
100 MPa14.5 ksi

Izod Impact, Notched

15 J/m0.28 ft·lbf/in
32 J/m0.6 ft·lbf/in

Hardness, Rockwell M

120 HRM
125 HRM

Same in both: Poisson's Ratio 0.34

Physical

Density and transition temperatures.

Density

1.5 g/cm³0.05 lb/in³
1.3 g/cm³0.05 lb/in³

Glass Transition (Tg)

220°C428 °F
427°C801 °F

Water Absorption (Saturation)

1.6%
5%

Same in both: Water Absorption (24 h) 0.4%

Thermal

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

Thermal Conductivity

0.3 W/m·K0.17 BTU/hr·ft·°F
0.41 W/m·K0.24 BTU/hr·ft·°F

Specific Heat Capacity

1,600 J/kg·K0.38 BTU/lb·°F
1,000 J/kg·K0.24 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

40 µm/m·K22.2 µin/in·°F
23 µm/m·K12.8 µin/in·°F

Max Service Temperature (continuous)

130°C266 °F
310°C590 °F

Min Service Temperature

-40°C-40 °F
-196°C-321 °F

Heat Deflection Temp. @ 0.45 MPa

195°C383 °F
—

Heat Deflection Temp. @ 1.8 MPa

180°C356 °F
435°C815 °F

Limiting Oxygen Index

32%
58%

Max Service Temperature (short-term)

150°C302 °F
500°C932 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹¹ Ω·m3.94×10¹⁸ µΩ·in
1×10¹² Ω·m3.94×10¹⁹ µΩ·in

Dielectric Strength

13 kV/mm330 V/mil
22 kV/mm559 V/mil

Dielectric Constant (1 MHz)

6.5
3.2

Dissipation Factor (1 MHz)

0.035
0.004

Volume Resistivity

1×10¹³ Ω·cm
1×10¹⁴ Ω·cm

Surface Resistivity

1×10¹³ Ω
—

Comparative Tracking Index (CTI)

600 V
—

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

62 / 100
92 / 100

Same in both: UV / Weathering Resistance 70 / 100

Manufacturability

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

Machinability

45 / 100
50 / 100

Weldability

0 / 100
5 / 100

Polishability

80 / 100
55 / 100

Mold Shrinkage

0.8%
—

Processing Melt Temperature (typ.)

95°C203 °F
—

Mold Temperature (typ.)

155°C311 °F
—

Same in both: Formability (cold) 5 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

85 MJ/kg36,543 BTU/lb
—

Embodied Carbon (primary production)

4.5 kg CO₂/kg
—

Embodied Water

180 L/kg21.6 gal/lb
—

Same in both: Typical Recycled Content 0%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

41 kN·m/kg
123 kN·m/kg

Specific Stiffness (E / density)

5.7 MN·m/kg
4.5 MN·m/kg

Thermal Diffusivity

0.1 mm²/s
0.3 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 scalePBI

Manufacturing and finishing

CapabilityMF Moulding CompoundPBI
CNC machining—Yes
Sheet metal—Yes
Injection molding—Yes
Default condition—Unfilled
Relative cost$$ Standard$$$$$ Specialty
Min. machined wall—0.5 mm
Best machined surface—Ra 0.8 µm
Chrome Plating (Plastic)—Yes
EMI Shielding Coating—Yes
Painting—Yes
Soft Touch Coating—Yes
Spray Painting—Yes
UV Coating—Yes

MF Moulding Compound vs PBI — frequently asked

Is PBI stronger than MF Moulding Compound?

Yes. PBI has a typical tensile strength of 160 MPa (23.2 ksi) against 62 MPa (8.99 ksi) for MF Moulding Compound — about 158% more.

Which is cheaper, MF Moulding Compound or PBI?

MF Moulding Compound is the lower-cost material: it sits in the standard tier ($$) while PBI is specialty ($$$$$). 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, MF Moulding Compound or PBI?

PBI, by a small margin. Both rate fair for machinability — 50/100 against 45/100 for MF Moulding Compound; for welding the order is PBI first (not recommended, 5/100) then MF Moulding Compound (not recommended, 0/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in MF Moulding Compound and PBI 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.