Fiberglass/Phenolic Honeycomb (HRP)
also HRP
Fiberglass/Phenolic Honeycomb (HRP) is a woven glass fabric honeycomb impregnated with phenolic resin, supplied at densities of 3.0, 4.0, 5.5, 8.0 and 12.0 lb/ft³, with a default density of 0.064 g/cm³ and thermal conductivity of 0.055 W/m·K.
Reference datasheet — Fiberglass/Phenolic Honeycomb (HRP) is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the 4.0 condition
Fiberglass/Phenolic Honeycomb (HRP) grades and fills
Fiberglass/Phenolic Honeycomb (HRP) is supplied in 5 conditions, soft to hard. 4.0 is the default FabDigit quotes; the values on this page are for it.
Compare all 5 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
HRP-3/16-3.0 | Lightest HRP grade — non-structural or lightly loaded radome and fairing sandwich panels. | 2 | |||
4.0Default HRP-3/16-4.0 | Most common general-purpose HRP density — best balance of weight, shear stiffness and cost. | 4 | |||
HRP-3/16-5.5 | Mid-density structural grade for floor panels and moderately loaded fairings. | 6 | |||
HRP-3/16-8.0 | High-density grade for highly loaded joints, hard points and rotor/engine structures. | 12 | |||
HRP-3/16-12.0 | Maximum-strength HRP for local reinforcement, ramps and heavily loaded insert areas. | 20 |
What is Fiberglass/Phenolic Honeycomb (HRP)?
Fiberglass/Phenolic Honeycomb (HRP) is a woven glass fabric honeycomb impregnated with phenolic resin, supplied at densities of 3.0, 4.0, 5.5, 8.0 and 12.0 lb/ft³, with a default density of 0.064 g/cm³ and thermal conductivity of 0.055 W/m·K. Engineers specify it for fire-rated structural sandwich panels where its strength and moderate cost beat aramid core. The glass fabric is highly abrasive to cutting tools, the core must be adhesively bonded rather than welded, and exposed edges need potting against moisture. HRH-49 aramid honeycomb is the alternative when weight and impact tolerance dominate. Fiberglass/Phenolic Honeycomb (HRP) has a density of 0.06 g/cm³ (0.0023 lb/in³), lighter than 92% of composite grades. Its glass-transition temperature is 180°C (356 °F). Fiberglass/Phenolic Honeycomb (HRP) has a tensile strength of 4 MPa (0.537 ksi), weaker than 87% of composite grades. The elastic modulus is 0.28 GPa (0.04 Msi).
What is Fiberglass/Phenolic Honeycomb (HRP) used for?
- fire-rated aircraft panels
- marine bulkhead panels
- industrial sandwich enclosures
- rail interior panels
Advantages
- Lightweight — 0.06 g/cm³ (0.0023 lb/in³), better than 92% of composite grades
- Low embodied carbon — 4.5 kg CO₂/kg, better than 79% of composite grades
Limitations
- Low stiffness — 0.28 GPa (0.04 Msi), worse than 88% of composite grades
- Poor heat conductor — 0.06 W/m·K (0.0318 BTU/hr·ft·°F), worse than 83% of composite grades
Fiberglass/Phenolic Honeycomb (HRP) properties
Typical room-temperature values for Fiberglass/Phenolic Honeycomb (HRP)-4.0; bars are the position among composite grades.
Physical2
Fiberglass/Phenolic Honeycomb (HRP) has a density of 0.06 g/cm³ (0.0023 lb/in³), lighter than 92% of composite grades. Its glass-transition temperature is 180°C (356 °F).
Mechanical6
Fiberglass/Phenolic Honeycomb (HRP) has a tensile strength of 4 MPa (0.537 ksi), weaker than 87% of composite grades. The elastic modulus is 0.28 GPa (0.04 Msi).
Thermal6
Fiberglass/Phenolic Honeycomb (HRP) is rated for continuous service to 177°C (351 °F). It conducts heat at 0.06 W/m·K (0.0318 BTU/hr·ft·°F), worse than 83% of composite grades.
Electrical2
Fiberglass/Phenolic Honeycomb (HRP) has an electrical resistivity of 1×10¹⁰ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (80/100), better than 54% of composite grades. UV resistance is fair.
Sustainability3
Producing a kilogram of Fiberglass/Phenolic Honeycomb (HRP) takes about 60 MJ of energy and emits 4.5 kg of CO₂ — less than 97% of composite grades. Typical recycled content is 0%.
Manufacturability1
Fiberglass/Phenolic Honeycomb (HRP)'s machinability is fair (40/100, better than 57% of composite grades).
Common Calculations2
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the composite family
Yield strength against density for every composite grade FabDigit runs. Fiberglass/Phenolic Honeycomb (HRP) is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Fiberglass/Phenolic Honeycomb (HRP)
Is Fiberglass/Phenolic Honeycomb (HRP) easy to machine?
Cut with ultrasonic knife, hot-wire-free abrasive band or crush-grind/diamond-coated tooling with vacuum hold-down and cell filling (wax/ice) for contoured profiles; glass is highly abrasive on carbide.
Can Fiberglass/Phenolic Honeycomb (HRP) be welded?
Not weldable — cores are joined by film adhesive splicing, foaming adhesive, or potting compound at inserts and edges.
Can Fiberglass/Phenolic Honeycomb (HRP) be formed, bent or molded?
Overexpanded (OX) and flexible-core forms allow single-curvature drape; complex double curvature requires heat-forming, kerfing or machined core; co-cure or secondary-bond with 120–180 °C epoxy/phenolic film adhesive under vacuum/autoclave pressure.
Fiberglass/Phenolic Honeycomb (HRP) 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 |
|---|---|---|
| E-glass fabric (woven, silane finish)bias/plain weave scrim forming the cell walls | 50 – 65 | 58 |
| phenolic resin (resole, cured)multiple dip-and-cure impregnations set final density | ≥ 35 (balance) |
What surface finishes work on Fiberglass/Phenolic Honeycomb (HRP)?
Seal all exposed edges and fastener zones with potting epoxy to block moisture ingress; degrease and lightly abrade skins, no plating/anodizing applies to the core itself.
Equivalent designations
Standards and trade names that resolve to Fiberglass/Phenolic Honeycomb (HRP) in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- HRP
How much does Fiberglass/Phenolic Honeycomb (HRP) cost?
Fiberglass/Phenolic Honeycomb (HRP) is a high-cost composite ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Fiberglass/Phenolic Honeycomb (HRP) — frequently asked
What is Fiberglass/Phenolic Honeycomb (HRP) used for?
Fiberglass/Phenolic Honeycomb (HRP) is typically used for fire-rated aircraft panels, marine bulkhead panels, industrial sandwich enclosures and rail interior panels. In short: fire-resistant structural core; cheaper than aramid honeycomb; abrasive to cutting tools.
What is the tensile strength of Fiberglass/Phenolic Honeycomb (HRP)?
Fiberglass/Phenolic Honeycomb (HRP) has a typical tensile strength of 4 MPa (0.537 ksi) — weaker than 87% of composite grades. Strength varies by condition: see the 5 listed tempers.
Is Fiberglass/Phenolic Honeycomb (HRP) easy to machine?
Not especially — machinability is rated fair (40/100, better than 57% of composite grades). Cut with ultrasonic knife, hot-wire-free abrasive band or crush-grind/diamond-coated tooling with vacuum hold-down and cell filling (wax/ice) for contoured profiles; glass is highly abrasive on carbide.
Can Fiberglass/Phenolic Honeycomb (HRP) be welded?
Not weldable — cores are joined by film adhesive splicing, foaming adhesive, or potting compound at inserts and edges.
What surface finishes work on Fiberglass/Phenolic Honeycomb (HRP)?
Seal all exposed edges and fastener zones with potting epoxy to block moisture ingress; degrease and lightly abrade skins, no plating/anodizing applies to the core itself.
Can Fiberglass/Phenolic Honeycomb (HRP) be formed, bent or molded?
Overexpanded (OX) and flexible-core forms allow single-curvature drape; complex double curvature requires heat-forming, kerfing or machined core; co-cure or secondary-bond with 120–180 °C epoxy/phenolic film adhesive under vacuum/autoclave pressure.
What is the maximum service temperature of Fiberglass/Phenolic Honeycomb (HRP)?
Fiberglass/Phenolic Honeycomb (HRP) is rated for continuous use to about 177°C (351 °F), and briefly to 205°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Fiberglass/Phenolic Honeycomb (HRP) cost?
Fiberglass/Phenolic Honeycomb (HRP) is a high-cost composite ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- HexWeb HRP Glass Fabric/Phenolic Honeycomb Product Data — Hexcel (2020)
- ASTM C365 — Flatwise Compressive Properties of Sandwich Cores — ASTM (2016)
- ASTM C273 — Shear Properties of Sandwich Core Materials — ASTM (2020)
- MIL-C-8073 / AMS-C-8073 Core Material, Plastic Honeycomb — SAE/US DoD (1998)
- MIL-HDBK-23 / CMH-17 Vol.6 Sandwich Structures — SAE International (2013)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.