FabDigit

Quartz Fiber Composite

Quartz Fiber Composite reinforces high-purity fused-silica fabric with epoxy, cyanate ester, polyimide, phenolic or PTFE matrices, and is also available as silica/silica ceramic and as bare fabric.

High cost $$$$

Reference datasheet — Quartz Fiber Composite 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 QF-EP condition

Quartz Fiber Composite grades and fills

Quartz Fiber Composite is supplied in 7 conditions, soft to hard. QF-EP is the default FabDigit quotes; the values on this page are for it.

Compare all 7 grades and fillsHide
Grade · open for datasheetBest forYield MPaTensile MPaElong. %Hardness
SiO₂f/SiO₂
All-ceramic quartz composite for hypersonic missile radomes — 1000 °C+ service and very low loss, but low strength and porous/moisture-sensitive without sealing.40
quartz fabric reinforced PTFE microwave laminate
Pick for mm-wave PCBs and low-loss RF laminates where tanδ below 0.002 and near-zero moisture uptake are required.90
quartz fabric / phenolic (ablative) laminate
Ablative and fire-barrier grade for nose cones, nozzle liners and hot radome sections; higher dielectric loss than epoxy/CE.300
quartz fabric / polyimide or bismaleimide laminate
For continuous 250–300 °C service radomes and high-temperature RF structures where epoxy/CE Tg is insufficient.480
QF-EPDefault
quartz fabric / epoxy laminate
Standard low-cost radome and microwave-window laminate; use up to ~150 °C where loss tangent ~0.01 is acceptable.500
quartz fabric / cyanate ester laminate
Choose for the lowest loss tangent and lowest moisture pickup in high-performance radomes and space antennas up to ~230 °C.520
Dry quartz fiber / fabric
The bare reinforcement — yarn, roving, woven fabric or tape used for prepregging, filament winding, thermal insulation and high-temperature sleeving.3,4004

What is Quartz Fiber Composite?

Quartz Fiber Composite reinforces high-purity fused-silica fabric with epoxy, cyanate ester, polyimide, phenolic or PTFE matrices, and is also available as silica/silica ceramic and as bare fabric. It is chosen for RF and microwave transparency, low dielectric loss and thermal stability: 500 MPa tensile strength, 25 GPa modulus, 1.75 g/cm3 density, 135 C glass transition and 150 C service in the standard epoxy form. Stiffness and strength are low compared with carbon or aramid laminates, the fiber is very abrasive to machine (machinability score 25), and material cost is high. E-glass laminates are the cheaper option where dielectric loss is not critical. Quartz Fiber Composite has a density of 1.75 g/cm³ (0.0632 lb/in³), lighter than 51% of composite grades. Its glass-transition temperature is 135°C (275 °F). Quartz Fiber Composite has a tensile strength of 500 MPa (72.5 ksi), stronger than 66% of composite grades. Elongation at break is 2% and the elastic modulus is 25 GPa (3.63 Msi).

What is Quartz Fiber Composite used for?

  • radomes
  • printed circuit substrates
  • high-temperature insulation
  • ballistic/thermal shielding

Quartz Fiber Composite properties

Typical room-temperature values for Quartz Fiber Composite-QF-EP; bars are the position among composite grades.

Physical4

Quartz Fiber Composite has a density of 1.75 g/cm³ (0.0632 lb/in³), lighter than 51% of composite grades. Its glass-transition temperature is 135°C (275 °F).

Density1.75 g/cm³0.06 lb/in³
Glass Transition (Tg)135°C275 °F
Water Absorption (24 h)0.15%
Water Absorption (Saturation)0.6%

Mechanical10

Quartz Fiber Composite has a tensile strength of 500 MPa (72.5 ksi), stronger than 66% of composite grades. Elongation at break is 2% and the elastic modulus is 25 GPa (3.63 Msi).

Elastic (Young's) Modulus25 GPa3.6 Msi
Shear Modulus4 GPa0.58 Msi
Poisson's Ratio0.16
Tensile Strength (Ultimate)500 MPa72.5 ksi
Elongation at Break2%
Compressive Strength400 MPa58 ksi
Compressive Modulus24 GPa3.5 Msi
Flexural Strength550 MPa79.8 ksi
Flexural Modulus24 GPa3.5 Msi
Shear Strength45 MPa6.5 ksi

Thermal8

Quartz Fiber Composite is rated for continuous service to 150°C (302 °F). It conducts heat at 0.4 W/m·K (0.231 BTU/hr·ft·°F), better than 53% of composite grades. Thermal expansion is 4 µm/m·K (2.22 µin/in·°F).

Thermal Conductivity0.4 W/m·K0.23 BTU/hr·ft·°F
Specific Heat Capacity900 J/kg·K0.21 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)4 µm/m·K2.2 µin/in·°F
Max Service Temperature (continuous)150°C302 °F
Min Service Temperature-196°C-321 °F
Flammability (UL 94)HB with standard epoxy; V-0 achievable with brominated/phosphorus flame-retardant epoxy or with phenolic/PI matrix
Limiting Oxygen Index32%
Max Service Temperature (short-term)200°C392 °F

Electrical6

Quartz Fiber Composite is an electrical insulator with a dielectric strength of 20 kV/mm (508 V/mil) and a resistivity of 1×10¹³ Ω·m.

Electrical Resistivity1×10¹³ Ω·m3.94×10²⁰ µΩ·in
Dielectric Strength20 kV/mm508 V/mil
Dielectric Constant (1 MHz)3.2
Dissipation Factor (1 MHz)0.01
Volume Resistivity1×10¹⁵ Ω·cm
Surface Resistivity1×10¹⁴ Ω

Chemical & Environmental3

Corrosion resistance is excellent (85/100), better than 65% of composite grades. UV resistance is good.

Corrosion ResistanceExcellent85/100
UV / Weathering ResistanceGood55/100
Chemical Resistance SummaryFiber is essentially inert fused silica — excellent to water, acids and solvents, but attacked by HF, hot concentrated phosphoric acid and strong alkali; overall resistance is limited by the resin matrix (epoxy: good to dilute acids/fuels, poor to strong bases and hot solvents).

Sustainability4

Producing a kilogram of Quartz Fiber Composite takes about 320 MJ of energy and emits 22 kg of CO₂ — more than 72% of composite grades. Typical recycled content is 0%.

Embodied Energy (primary production)320 MJ/kg137,575 BTU/lb
Embodied Carbon (primary production)22 kg CO₂/kg
Embodied Water250 L/kg30 gal/lb
Typical Recycled Content0%

Manufacturability2

Quartz Fiber Composite's machinability is poor (25/100, worse than 65% of composite grades).

MachinabilityPoor25/100
PolishabilityFair35/100

Common Calculations4

Specific Strength (UTS / density)calculated286 kN·m/kg
Specific Stiffness (E / density)calculated14.3 MN·m/kg
Thermal Diffusivitycalculated0.3 mm²/s
Thermal Shock Resistance Indexcalculated2

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. Quartz Fiber Composite is highlighted; hover a dot for its name, or open the interactive family chart.

1101001,000510Density (g/cm³)Yield strength (MPa) — log scale

Working with Quartz Fiber Composite

Is Quartz Fiber Composite easy to machine?

Extremely abrasive and prone to fiber fuzzing — use diamond-coated or PCD tooling, abrasive waterjet or diamond grinding, with dust extraction; carbide tools wear in minutes.

Can Quartz Fiber Composite be welded?

Not weldable; join by adhesive bonding (film epoxy), co-curing, or mechanical fastening with bushed/potted holes.

Can Quartz Fiber Composite be formed, bent or molded?

Processed as prepreg autoclave/press lay-up, RTM/VARTM or filament winding; fabric drapes well but the resin-rich low-void cure is critical for stable dielectric performance.

Quartz Fiber Composite 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
SiO2 (quartz fiber)fiber weight fraction of laminate; fiber purity ≥99.95% SiO₂60 – 7268
silane sizingcoupling agent on fiber surface0.1 – 10.4
Al2O3+Na2O+Fe2O3 (fiber impurities)total metal-oxide impurity in fused silica fiber0 – 0.050.02
epoxy resin (matrix)replaced by cyanate ester / BMI / polyimide / phenolic / PTFE in other variants≥ 28 (balance)

What surface finishes work on Quartz Fiber Composite?

Seal edges and machined holes against moisture ingress; radomes are typically painted with thin RF-transparent polyurethane or rain-erosion coatings; PTFE grades are copper-clad and plasma/etch treated.

Equivalent designations

Standards and trade names that resolve to Quartz Fiber Composite in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.

Also called
Quartz fiber

How much does Quartz Fiber Composite cost?

Quartz Fiber Composite 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.

Quartz Fiber Composite — frequently asked

What is Quartz Fiber Composite used for?

Quartz Fiber Composite is typically used for radomes, printed circuit substrates, high-temperature insulation and ballistic/thermal shielding. In short: lowest dielectric loss laminate; RF-transparent radome material; low stiffness versus carbon.

What is the tensile strength of Quartz Fiber Composite?

Quartz Fiber Composite has a typical tensile strength of 500 MPa (72.5 ksi) — stronger than 66% of composite grades. Strength varies by condition: see the 7 listed tempers.

Is Quartz Fiber Composite easy to machine?

Not especially — machinability is rated poor (25/100, worse than 65% of composite grades). Extremely abrasive and prone to fiber fuzzing — use diamond-coated or PCD tooling, abrasive waterjet or diamond grinding, with dust extraction; carbide tools wear in minutes.

Can Quartz Fiber Composite be welded?

Not weldable; join by adhesive bonding (film epoxy), co-curing, or mechanical fastening with bushed/potted holes.

What surface finishes work on Quartz Fiber Composite?

Seal edges and machined holes against moisture ingress; radomes are typically painted with thin RF-transparent polyurethane or rain-erosion coatings; PTFE grades are copper-clad and plasma/etch treated.

Can Quartz Fiber Composite be formed, bent or molded?

Processed as prepreg autoclave/press lay-up, RTM/VARTM or filament winding; fabric drapes well but the resin-rich low-void cure is critical for stable dielectric performance.

What is the maximum service temperature of Quartz Fiber Composite?

Quartz Fiber Composite 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.

How much does Quartz Fiber Composite cost?

Quartz Fiber Composite 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

  1. Quartzel Fused Quartz Yarn and Fabric technical data — Saint-Gobain Quartz (2022)
  2. Astroquartz III quartz fiber and fabric data sheets — JPS Composite Materials (2021)
  3. ASM Handbook Vol. 21: Composites — ASM International (2001)
  4. Radome Engineering Handbook / Microwave Materials chapters — Various (2010)

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.