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G5 Melamine Matrix

Properties of the Melamine Matrix condition, compared with the other G5 grades.

Standard choice when arc resistance, tracking resistance and inherent flame retardance matter more than humid-state electrical stability.

CNC machiningSheet metalPremium cost $$$

What is G5 Melamine Matrix?

G5 Melamine Matrix is G5 in the Melamine Matrix condition — standard choice when arc resistance, tracking resistance and inherent flame retardance matter more than humid-state electrical stability. G5 Melamine Matrix has a tensile strength of 220 MPa (31.9 ksi), weaker than 57% of composite grades. Elongation at break is 1.5% and the elastic modulus is 17 GPa (2.47 Msi). G5 Melamine Matrix has a density of 1.95 g/cm³ (0.0704 lb/in³), heavier than 74% of composite grades.

Advantages

  • Low embodied carbon — 4.5 kg CO₂/kg, better than 79% of composite grades

Limitations

  • Needs corrosion protection — 58/100, worse than 82% of composite grades

G5 Melamine Matrix properties

Typical room-temperature values for G5 Melamine Matrix — 10 properties are specific to this condition; the rest are grade-level values shared by every G5 grade. Each bar shows where the value sits among the composite grades in FabDigit's library — further right is higher.

Physical3

G5 Melamine Matrix has a density of 1.95 g/cm³ (0.0704 lb/in³), heavier than 74% of composite grades.

Density1.95 g/cm³0.07 lb/in³
Water Absorption (24 h)0.9%
Water Absorption (Saturation)2%

Mechanical12

G5 Melamine Matrix has a tensile strength of 220 MPa (31.9 ksi), weaker than 57% of composite grades. Elongation at break is 1.5% and the elastic modulus is 17 GPa (2.47 Msi).

Elastic (Young's) Modulus17 GPa2.5 Msi
Shear Modulus6 GPa0.87 Msi
Poisson's Ratio0.17
Tensile Strength (Ultimate)220 MPa31.9 ksi
Elongation at Break1.5%
Compressive Strength415 MPa60.2 ksi
Compressive Modulus16 GPa2.3 Msi
Flexural Strength310 MPa45 ksi
Flexural Modulus18 GPa2.6 Msi
Shear Strength125 MPa18.1 ksi
Izod Impact, Notched550 J/m10.3 ft·lbf/in
Hardness, Rockwell M115 HRM

Thermal8

G5 Melamine Matrix is rated for continuous service to 150°C (302 °F). It conducts heat at 0.35 W/m·K (0.202 BTU/hr·ft·°F), better than 50% of composite grades. Thermal expansion is 14 µm/m·K (7.78 µin/in·°F).

Thermal Conductivity0.35 W/m·K0.2 BTU/hr·ft·°F
Specific Heat Capacity1,100 J/kg·K0.26 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)14 µm/m·K7.8 µin/in·°F
Max Service Temperature (continuous)150°C302 °F
Min Service Temperature-60°C-76 °F
Flammability (UL 94)V-0 typical
Limiting Oxygen Index45%
Max Service Temperature (short-term)200°C392 °F

Electrical7

G5 Melamine Matrix is an electrical insulator with a dielectric strength of 15 kV/mm (381 V/mil) and a resistivity of 1×10¹¹ Ω·m.

Electrical Resistivity1×10¹¹ Ω·m3.94×10¹⁸ µΩ·in
Dielectric Strength15 kV/mm381 V/mil
Dielectric Constant (1 MHz)7.5
Dissipation Factor (1 MHz)0.03
Volume Resistivity1×10¹³ Ω·cm
Surface Resistivity1×10¹² Ω
Comparative Tracking Index (CTI)600 V

Chemical & Environmental3

Corrosion resistance is good (58/100), worse than 82% of composite grades. UV resistance is fair.

Corrosion ResistanceGood58/100
UV / Weathering ResistanceFair45/100
Chemical Resistance SummaryGood against mineral oils, aliphatic solvents and weak acids; attacked by hot water/steam, strong alkalis and strong acids (resin hydrolysis); not for continuous immersion service.

Sustainability3

Producing a kilogram of G5 Melamine Matrix takes about 75 MJ of energy and emits 4.5 kg of CO₂ — less than 91% of composite grades. Typical recycled content is 0%.

Embodied Energy (primary production)75 MJ/kg32,244 BTU/lb
Embodied Carbon (primary production)4.5 kg CO₂/kg
Typical Recycled Content0%

Manufacturability2

G5 Melamine Matrix's machinability is poor (25/100, worse than 65% of composite grades).

MachinabilityPoor25/100
PolishabilityPoor30/100

Common Calculations4

Specific Strength (UTS / density)calculated113 kN·m/kg
Specific Stiffness (E / density)calculated8.7 MN·m/kg
Thermal Diffusivitycalculated0.2 mm²/s
Thermal Shock Resistance Indexcalculated0

Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.

Other G5 grades and fills

G5 is also supplied in 1 other condition. The full side-by-side table is on the G5 overview.

Working with G5 Melamine Matrix

Is G5 easy to machine?

Machine dry with sharp carbide or diamond tooling, high speed / moderate feed, backing plate to avoid edge chipping and delamination; provide dust extraction (glass + melamine dust is irritant).

Can G5 be welded?

Not weldable — thermoset laminate; join by bolting, riveting or epoxy bonding after abrading and solvent-cleaning the surface.

Can G5 be formed, bent or molded?

Supplied as fully cured flat sheet, rod or tube; no post-forming possible, all geometry by machining, punching (thin sheet, warm) or waterjet.

What surface finishes work on G5?

Edges should be deburred and sealed with varnish or epoxy to limit moisture pickup; can be sanded but not polished to gloss; paint only over abraded, dry surfaces.

G5 chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
E-glass woven fabricreinforcement, plain/twill weave cloth50 – 6558
melamine-formaldehyde resinmatrix; may be modified with phenolic for toughness≥ 35 (balance)

G5 Melamine Matrix — frequently asked

What is G5 Melamine Matrix used for?

G5 Melamine Matrix is typically used for arc barriers, switchgear insulators, terminal blocks and boards, punched washers and spacers, contactor and circuit breaker components and bus bar supports. In short: melamine arc-resistant laminate.

What is the tensile strength of G5 Melamine Matrix?

G5 Melamine Matrix has a typical tensile strength of 220 MPa (31.9 ksi) — weaker than 57% of composite grades. Strength varies by condition: see the 2 listed tempers.

Is G5 Melamine Matrix easy to machine?

Not especially — machinability is rated poor (25/100, worse than 65% of composite grades). Machine dry with sharp carbide or diamond tooling, high speed / moderate feed, backing plate to avoid edge chipping and delamination; provide dust extraction (glass + melamine dust is irritant).

Can G5 Melamine Matrix be welded?

Not weldable — thermoset laminate; join by bolting, riveting or epoxy bonding after abrading and solvent-cleaning the surface.

What surface finishes work on G5 Melamine Matrix?

Edges should be deburred and sealed with varnish or epoxy to limit moisture pickup; can be sanded but not polished to gloss; paint only over abraded, dry surfaces.

Can G5 Melamine Matrix be formed, bent or molded?

Supplied as fully cured flat sheet, rod or tube; no post-forming possible, all geometry by machining, punching (thin sheet, warm) or waterjet.

What is the maximum service temperature of G5 Melamine Matrix?

G5 Melamine Matrix is rated for continuous use to about 150°C (302 °F), and briefly to 200°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Can FabDigit make parts in G5 Melamine Matrix?

Yes — G5 Melamine Matrix is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.

Sources

  1. NEMA LI 1 — Industrial Laminated Thermosetting ProductsNEMA (1998)
  2. MIL-I-24768/9 (Type GME) and /8 (Type GMG) — Plastic Sheet, Laminated, ThermosettingUS DoD (1994)
  3. ASTM D709 — Laminated Thermosetting MaterialsASTM (2017)
  4. Melamine glass-cloth laminate (G5/G9) sheet datasheetindustrial laminate producers (2023)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.