G5 vs G7
Composite · grade comparison
G5 and G7 are both composite grades. G5 is the stronger of the two: tensile strength 220 MPa (31.9 ksi) against 170 MPa (24.7 ksi) for G7, about 29% more. G7 is lighter (1.8 g/cm³ vs 1.95 g/cm³ for G5) and G5 is stiffer (17 GPa vs 14 GPa). On the shop floor, G7 machines more easily (fair vs poor).
G5Choose it when strength drives the design.
G7Choose it when weight is the constraint, or when the part sees heat.
G5 vs G7: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all composite 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 composite 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
Shear Modulus
Tensile Strength (Ultimate)
Elongation at Break
Compressive Strength
Compressive Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Fracture Toughness (K_IC)
Izod Impact, Notched
Hardness, Rockwell M
Same in both: Poisson's Ratio 0.17
Physical
Density and transition temperatures.
Density
Water Absorption (24 h)
Water Absorption (Saturation)
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Heat Deflection Temp. @ 1.8 MPa
Limiting Oxygen Index
Max Service Temperature (short-term)
Same in both: Min Service Temperature -60°C-76 °F
Electrical
Conductivity and insulation.
Dielectric Constant (1 MHz)
Dissipation Factor (1 MHz)
Same in both: Electrical Resistivity 1×10¹¹ Ω·m3.94×10¹⁸ µΩ·in · Dielectric Strength 15 kV/mm381 V/mil · Volume Resistivity 1×10¹³ Ω·cm · Surface Resistivity 1×10¹² Ω · Comparative Tracking Index (CTI) 600 V
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
UV / Weathering Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Same in both: Typical Recycled Content 0%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Same in both: Thermal Diffusivity 0.2 mm²/s · Thermal Shock Resistance Index 0
Strength versus weight
Yield strength against density for every composite grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | G5 | G7 |
|---|---|---|
| Default condition | Melamine Matrix | Silicone Matrix |
| Relative cost | $$$ Premium | $$$ Premium |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both are offered for CNC machining and Sheet metal. Both take the same 1 finish: Painting.
G5 vs G7 — frequently asked
Is G5 stronger than G7?
Yes. G5 has a typical tensile strength of 220 MPa (31.9 ksi) against 170 MPa (24.7 ksi) for G7 — about 29% more.
Which is cheaper, G5 or G7?
Both sit in the same relative cost tier ($$$, premium); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, G5 or G7?
G7. Its machinability rates fair (35/100) against poor (25/100) for G5.
Ready to make it?
Upload a CAD file and FabDigit prices the part in G5 and G7 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.