Ultem 1000 GF20 vs Ultem 1000 GF30
Polymer · Ultem 1000 grade comparison
Ultem 1000 GF20 and Ultem 1000 GF30 are two grades of the same polymer grade, Ultem 1000: GF20 (20% glass-fiber reinforced) versus GF30 (30% glass-fiber reinforced). The chemistry is identical, so every difference below comes from the condition. Ultem 1000 GF30 is the stronger of the two: tensile strength 169 MPa (24.5 ksi) against 152 MPa (22 ksi) for Ultem 1000 GF20, about 11% more. In exchange, Ultem 1000 GF20 is the more ductile: elongation 4% versus 3% for Ultem 1000 GF30. Ultem 1000 GF20 is lighter (1.42 g/cm³ vs 1.51 g/cm³ for Ultem 1000 GF30) and Ultem 1000 GF30 is stiffer (9 GPa vs 6.9 GPa).
Ultem 1000 GF20Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
Ultem 1000 GF30Choose it when strength drives the design.
Ultem 1000 GF20 vs Ultem 1000 GF30: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Ultem 1000 GF20Ultem 1000 GF30
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Tensile Strength (Ultimate)
Elongation at Break
Compressive Strength
Flexural Strength
Flexural Modulus
Izod Impact, Notched
Hardness, Rockwell M
Same in both: Shear Modulus 1.2 GPa0.17 Msi · Bulk Modulus 4 GPa0.55 Msi · Poisson's Ratio 0.36 · Yield Strength (0.2% offset) 105 MPa15.2 ksi · Compressive Modulus 2.9 GPa0.42 Msi · Shear Strength 90 MPa13.1 ksi · Fracture Toughness (K_IC) 3.3 MPa·√m3 ksi·√in · Hardness, Shore D 87 Shore D · Hardness, Rockwell R 125 HRR
Physical
Density and transition temperatures.
Density
Same in both: Glass Transition (Tg) 217°C423 °F · Water Absorption (24 h) 0.25% · Water Absorption (Saturation) 1.25% · Refractive Index 1.66 · Light Transmission 78%
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Same in both: Specific Heat Capacity 1,100 J/kg·K0.26 BTU/lb·°F · Max Service Temperature (continuous) 170°C338 °F · Min Service Temperature -50°C-58 °F · Vicat Softening Point (B50) 219°C426 °F · Limiting Oxygen Index 47% · Max Service Temperature (short-term) 200°C392 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Resistivity 1×10¹⁵ Ω·m3.94×10²² µΩ·in · Dielectric Strength 33 kV/mm838 V/mil · Dielectric Constant (1 MHz) 3.15 · Dissipation Factor (1 MHz) 0.0013 · Volume Resistivity 1×10¹⁷ Ω·cm · Surface Resistivity 1×10¹⁶ Ω · Comparative Tracking Index (CTI) 175 V
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Corrosion Resistance 85 / 100 · UV / Weathering Resistance 35 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Mold Shrinkage
Same in both: Weldability 60 / 100 · Formability (cold) 50 / 100 · Polishability 80 / 100 · Melt Flow Rate 9 g/10 min · Processing Melt Temperature (typ.) 370°C698 °F · Mold Temperature (typ.) 150°C302 °F
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 250 MJ/kg107,481 BTU/lb · Embodied Carbon (primary production) 8.5 kg CO₂/kg · Embodied Water 500 L/kg59.9 gal/lb · Typical Recycled Content 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.
Ultem 1000 GF20 vs Ultem 1000 GF30 — frequently asked
Is Ultem 1000 GF30 stronger than Ultem 1000 GF20?
Yes. Ultem 1000 GF30 has a typical tensile strength of 169 MPa (24.5 ksi) against 152 MPa (22 ksi) for Ultem 1000 GF20 — about 11% more.
Which grade does FabDigit quote by default, GF20 or GF30?
Specify the condition in the material field or the drawing note; FabDigit prices the quote for the state you call out.
Which is easier to machine, Ultem 1000 GF20 or Ultem 1000 GF30?
Ultem 1000 GF20, by a small margin. Both rate fair for machinability — 48/100 against 42/100 for Ultem 1000 GF30.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Ultem 1000 GF20 and Ultem 1000 GF30 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.