Xydar GF15 vs Xydar GF40
Polymer · Xydar grade comparison
Xydar GF15 and Xydar GF40 are two grades of the same polymer grade, Xydar: GF15 (15 % glass-fiber reinforced) versus GF40 (40 % glass-fiber reinforced). The chemistry is identical, so every difference below comes from the condition. Xydar GF40 is the stronger of the two: tensile strength 155 MPa (22.5 ksi) against 145 MPa (21 ksi) for Xydar GF15, about 7% more. In exchange, Xydar GF15 is the more ductile: elongation 2.8% versus 1.6% for Xydar GF40. Xydar GF15 is lighter (1.5 g/cm³ vs 1.75 g/cm³ for Xydar GF40) and Xydar GF40 is stiffer (17 GPa vs 13.5 GPa). On the shop floor, Xydar GF15 machines more easily (fair vs poor).
Xydar GF15Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
Xydar GF40Choose it when strength drives the design.
Xydar GF15 vs Xydar GF40: 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.
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
Shear Strength
Izod Impact, Notched
Hardness, Shore D
Hardness, Rockwell M
Same in both: Poisson's Ratio 0.35 · Fracture Toughness (K_IC) 2.5 MPa·√m2.3 ksi·√in
Physical
Density and transition temperatures.
Density
Same in both: Melting Temperature (Tm) 350°C662 °F · Glass Transition (Tg) 135°C275 °F · Water Absorption (24 h) 0.03% · Water Absorption (Saturation) 0.1%
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Limiting Oxygen Index
Same in both: Specific Heat Capacity 1,150 J/kg·K0.27 BTU/lb·°F · Min Service Temperature -100°C-148 °F · Max Service Temperature (short-term) 300°C572 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Resistivity 1×10¹³ Ω·m3.94×10²⁰ µΩ·in · Dielectric Strength 35 kV/mm889 V/mil · Dielectric Constant (1 MHz) 3.7 · Dissipation Factor (1 MHz) 0.005 · Volume Resistivity 1×10¹⁵ Ω·cm · Surface Resistivity 1×10¹⁵ Ω · Comparative Tracking Index (CTI) 200 V
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Corrosion Resistance 92 / 100 · UV / Weathering Resistance 55 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Mold Shrinkage
Same in both: Polishability 40 / 100 · Processing Melt Temperature (typ.) 380°C716 °F · Mold Temperature (typ.) 120°C248 °F
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 220 MJ/kg94,583 BTU/lb · Embodied Carbon (primary production) 10 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.
Xydar GF15 vs Xydar GF40 — frequently asked
Is Xydar GF40 stronger than Xydar GF15?
Yes. Xydar GF40 has a typical tensile strength of 155 MPa (22.5 ksi) against 145 MPa (21 ksi) for Xydar GF15 — about 7% more.
Which grade does FabDigit quote by default, GF15 or GF40?
NEAT is the default Xydar condition in the FabDigit quote flow (neither GF15 nor GF40). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.
Which is easier to machine, Xydar GF15 or Xydar GF40?
Xydar GF15. Its machinability rates fair (45/100) against poor (30/100) for Xydar GF40; for welding the order is Xydar GF15 first (poor, 20/100) then Xydar GF40 (poor, 15/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in Xydar GF15 and Xydar GF40 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.