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PBT-GF30 vs PETG

Polymer · grade comparison

PBT-GF30 and PETG are both polymer grades. PBT-GF30 is the stronger of the two: tensile strength 130 MPa (18.9 ksi) against 50 MPa (7.25 ksi) for PETG, about 160% more. In exchange, PETG is the more ductile: elongation 120% versus 3% for PBT-GF30, and PBT-GF30 is harder (85 Shore D vs 78 Shore D). PETG is lighter (1.27 g/cm³ vs 1.53 g/cm³ for PBT-GF30) and PBT-GF30 is stiffer (10 GPa vs 2.1 GPa). On the shop floor, PETG machines more easily (65 vs 55 out of 100), PETG welds better (very good vs fair), and PETG sits in a lower cost tier (budget, $) than PBT-GF30 (standard, $$).

PBT-GF30Choose it when strength drives the design, or when the part sees heat.

PETGChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

PBT-GF30 vs PETG: properties

PBT-GF30PETG

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

10 GPa1.5 Msi
2.1 GPa0.3 Msi

Shear Modulus

3.6 GPa0.52 Msi
0.77 GPa0.11 Msi

Poisson's Ratio

0.38
0.4

Tensile Strength (Ultimate)

130 MPa18.9 ksi
50 MPa7.3 ksi

Elongation at Break

3%
120%

Compressive Strength

130 MPa18.9 ksi
60 MPa8.7 ksi

Compressive Modulus

8.5 GPa1.2 Msi
—

Flexural Strength

200 MPa29 ksi
70 MPa10.2 ksi

Flexural Modulus

9 GPa1.3 Msi
2.1 GPa0.3 Msi

Shear Strength

60 MPa8.7 ksi
—

Fracture Toughness (K_IC)

3.5 MPa·√m3.2 ksi·√in
—

Izod Impact, Notched

90 J/m1.7 ft·lbf/in
95 J/m1.8 ft·lbf/in

Hardness, Shore D

85 Shore D
78 Shore D

Hardness, Rockwell M

90 HRM
—

Hardness, Rockwell R

120 HRR
115 HRR

Yield Strength (0.2% offset)

—
50 MPa7.3 ksi

Physical

Density and transition temperatures.

Density

1.53 g/cm³0.06 lb/in³
1.27 g/cm³0.05 lb/in³

Melting Temperature (Tm)

225°C437 °F
—

Glass Transition (Tg)

50°C122 °F
80°C176 °F

Water Absorption (24 h)

0.06%
0.13%

Water Absorption (Saturation)

0.35%
0.5%

Refractive Index

—
1.57

Light Transmission

—
89%

Thermal

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

Thermal Conductivity

0.25 W/m·K0.14 BTU/hr·ft·°F
0.2 W/m·K0.12 BTU/hr·ft·°F

Specific Heat Capacity

1,400 J/kg·K0.33 BTU/lb·°F
1,200 J/kg·K0.29 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

25 µm/m·K13.9 µin/in·°F
68 µm/m·K37.8 µin/in·°F

Max Service Temperature (continuous)

130°C266 °F
63°C145 °F

Heat Deflection Temp. @ 0.45 MPa

215°C419 °F
70°C158 °F

Heat Deflection Temp. @ 1.8 MPa

207°C405 °F
64°C147 °F

Vicat Softening Point (B50)

200°C392 °F
82°C180 °F

Limiting Oxygen Index

22%
23%

Max Service Temperature (short-term)

190°C374 °F
75°C167 °F

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

Electrical

Conductivity and insulation.

Dielectric Strength

30 kV/mm762 V/mil
16 kV/mm406 V/mil

Dielectric Constant (1 MHz)

3.7
2.8

Surface Resistivity

1×10¹⁵ Ω
1×10¹⁶ Ω

Comparative Tracking Index (CTI)

550 V
—

Same in both: Electrical Resistivity 1×10¹⁴ Ω·m3.94×10²¹ µΩ·in · Dissipation Factor (1 MHz) 0.02 · Volume Resistivity 1×10¹⁶ Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

82 / 100
85 / 100

UV / Weathering Resistance

30 / 100
45 / 100

Manufacturability

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

Machinability

55 / 100
65 / 100

Weldability

45 / 100
80 / 100

Formability (cold)

10 / 100
88 / 100

Polishability

30 / 100
72 / 100

Mold Shrinkage

0.4%
0.35%

Melt Flow Rate

20 g/10 min
—

Processing Melt Temperature (typ.)

260°C500 °F
245°C473 °F

Mold Temperature (typ.)

80°C176 °F
25°C77 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

85 MJ/kg36,543 BTU/lb
84 MJ/kg36,114 BTU/lb

Embodied Carbon (primary production)

4.4 kg CO₂/kg
3.2 kg CO₂/kg

Embodied Water

200 L/kg24 gal/lb
210 L/kg25.2 gal/lb

Typical Recycled Content

5%
0%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

85 kN·m/kg
39 kN·m/kg

Specific Stiffness (E / density)

6.5 MN·m/kg
1.7 MN·m/kg

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 scalePETG

Manufacturing and finishing

CapabilityPBT-GF30PETG
CNC machining—Yes
Sheet metal—Yes
Injection molding—Yes
3D printing—Yes
Default condition—Unfilled
Relative cost$$ Standard$ Budget
Min. machined wall—0.5 mm
Best machined surface—Ra 0.8 µm
Chrome Plating (Plastic)—Yes
Conductive Coating—Yes
Dyeing (Nylon)—Yes
EMI Shielding Coating—Yes
Painting—Yes
Primer Coating—Yes
Soft Touch Coating—Yes
Spray Painting—Yes
Tinted Coating—Yes
UV Coating—Yes
Vacuum Metallization—Yes
Waterproof Coating—Yes

PBT-GF30 vs PETG — frequently asked

Is PBT-GF30 stronger than PETG?

Yes. PBT-GF30 has a typical tensile strength of 130 MPa (18.9 ksi) against 50 MPa (7.25 ksi) for PETG — about 160% more.

Which is cheaper, PBT-GF30 or PETG?

PETG is the lower-cost material: it sits in the budget tier ($) while PBT-GF30 is standard ($$). 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, PBT-GF30 or PETG?

PETG, by a small margin. Both rate good for machinability — 65/100 against 55/100 for PBT-GF30; for welding the order is PETG first (very good, 80/100) then PBT-GF30 (fair, 45/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in PBT-GF30 and PETG 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.