Phenolic XX · grade
Phenolic XX-XXX
Properties of the XXX condition, compared with the other Phenolic XX grades.
Pick for radio-frequency or humid-environment insulation where low loss and low moisture pickup matter more than strength.
What is Phenolic XX-XXX?
Phenolic XX-XXX is Phenolic XX in the XXX grade — pick for radio-frequency or humid-environment insulation where low loss and low moisture pickup matter more than strength. Phenolic XX-XXX has a tensile strength of 83 MPa (12 ksi), weaker than 80% of composite grades. Elongation at break is 1.5% and the elastic modulus is 7 GPa (1.02 Msi). Phenolic XX-XXX has a density of 1.34 g/cm³ (0.0484 lb/in³), lighter than 79% of composite grades. Its glass-transition temperature is 170°C (338 °F). Phenolic Matrix is the default condition FabDigit quotes; XXX is available on request or by drawing note.
Advantages
- Easy to machine — 80/100, better than 85% of composite grades
- Lightweight — 1.34 g/cm³ (0.0484 lb/in³), better than 79% of composite grades
- Low embodied carbon — 4.5 kg CO₂/kg, better than 79% of composite grades
Limitations
- Degrades in UV without stabilisers — 25/100, worse than 86% of composite grades
- Low stiffness — 7 GPa (1.02 Msi), worse than 79% of composite grades
- Limited service temperature — 120°C (248 °F), worse than 79% of composite grades
- Poor heat conductor — 0.25 W/m·K (0.144 BTU/hr·ft·°F), worse than 75% of composite grades
Phenolic XX-XXX properties
Typical room-temperature values for Phenolic XX-XXX — 8 properties are specific to this condition; the rest are grade-level values shared by every Phenolic XX grade. Each bar shows where the value sits among the composite grades in FabDigit's library — further right is higher.
Physical4
Phenolic XX-XXX has a density of 1.34 g/cm³ (0.0484 lb/in³), lighter than 79% of composite grades. Its glass-transition temperature is 170°C (338 °F).
Mechanical12
Phenolic XX-XXX has a tensile strength of 83 MPa (12 ksi), weaker than 80% of composite grades. Elongation at break is 1.5% and the elastic modulus is 7 GPa (1.02 Msi).
Thermal8
Phenolic XX-XXX is rated for continuous service to 120°C (248 °F). It conducts heat at 0.25 W/m·K (0.144 BTU/hr·ft·°F), worse than 75% of composite grades. Thermal expansion is 25 µm/m·K (13.9 µin/in·°F).
Electrical7
Phenolic XX-XXX is an electrical insulator with a dielectric strength of 18 kV/mm (457.2 V/mil) and a resistivity of 1×10⁹ Ω·m.
Chemical & Environmental3
Corrosion resistance is good (65/100), worse than 72% of composite grades. UV resistance is poor.
Sustainability3
Producing a kilogram of Phenolic XX-XXX takes about 80 MJ of energy and emits 4.5 kg of CO₂ — less than 84% of composite grades. Typical recycled content is 5%.
Manufacturability2
Phenolic XX-XXX's machinability is very good (80/100, better than 85% of composite grades).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other Phenolic XX grades and fills
Phenolic XX is also supplied in 5 other conditions. The full side-by-side table is on the Phenolic XX overview.
- Phenolic MatrixDefaultGeneral-purpose paper-phenolic sheet/rod/tube for combined mechanical and low-frequency electrical duty at low cost.90 MPa tensile
- XXXPick for radio-frequency or humid-environment insulation where low loss and low moisture pickup matter more than strength.83 MPa tensile
- XXXPPick for thin sheet that must be blanked/punched (terminal strips, washers) while keeping good electrical loss figures.80 MPa tensile
Working with Phenolic XX-XXX
Is Phenolic XX easy to machine?
Cuts, drills and turns easily with sharp carbide tooling at high speed and no coolant; dust is abrasive and irritating, so use vacuum extraction and back up holes to avoid edge chipping and delamination.
Can Phenolic XX be welded?
Thermoset — cannot be welded or thermally reformed; join by bolting, riveting or epoxy/phenolic adhesive bonding after abrading the surface.
Can Phenolic XX be formed, bent or molded?
Supplied as fully cured sheet, rod and tube; thin sheet (P/PC grades) can be hot- or cold-punched, but thick stock must be machined to shape.
What surface finishes work on Phenolic XX?
Sand or scrape edges to remove fuzz and seal machined surfaces with varnish/epoxy to limit moisture pickup; the natural finish is brown-to-black and not platable, though it accepts primer-based paint.
Phenolic XX 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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| phenol-formaldehyde resinresole/novolac, fully cured thermoset binder | 40 – 55 | 48 |
| volatiles/residual moisture | 0 – 2 | 1 |
| cellulose kraft paperreinforcement web, multiple plies | ≥ 45 (balance) | — |
Phenolic XX-XXX — frequently asked
What is Phenolic XX-XXX used for?
Phenolic XX-XXX is typically used for electrical insulators and barriers, terminal boards and tag strips, punched washers, gaskets and shims, coil and transformer spacers, switch and relay bases and low-load bushings and cams. In short: classic phenolic laminate.
What is the tensile strength of Phenolic XX-XXX?
Phenolic XX-XXX has a typical tensile strength of 83 MPa (12 ksi) — weaker than 80% of composite grades. Strength varies by condition: see the 6 listed tempers.
Is Phenolic XX-XXX easy to machine?
Yes — machinability is rated very good (80/100, better than 85% of composite grades). Cuts, drills and turns easily with sharp carbide tooling at high speed and no coolant; dust is abrasive and irritating, so use vacuum extraction and back up holes to avoid edge chipping and delamination.
Can Phenolic XX-XXX be welded?
Thermoset — cannot be welded or thermally reformed; join by bolting, riveting or epoxy/phenolic adhesive bonding after abrading the surface.
What surface finishes work on Phenolic XX-XXX?
Sand or scrape edges to remove fuzz and seal machined surfaces with varnish/epoxy to limit moisture pickup; the natural finish is brown-to-black and not platable, though it accepts primer-based paint.
Can Phenolic XX-XXX be formed, bent or molded?
Supplied as fully cured sheet, rod and tube; thin sheet (P/PC grades) can be hot- or cold-punched, but thick stock must be machined to shape.
What is the maximum service temperature of Phenolic XX-XXX?
Phenolic XX-XXX is rated for continuous use to about 120°C (248 °F), and briefly to 150°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in Phenolic XX-XXX?
Yes — Phenolic XX-XXX 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
- NEMA LI 1 — Industrial Laminating Thermosetting Products — NEMA (1998)
- ASTM D709 — Standard Specification for Laminated Thermosetting Materials — ASTM (2017)
- Paper-phenolic industrial laminate grades X / XX / XXX / XXXP — Norplex-Micarta (2022)
- Engineered Materials Handbook Vol. 2 — Engineering Plastics (phenolic laminates) — ASM International (1988)
- MatWeb paper-reinforced phenolic laminate property listings — MatWeb (2024)
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.