Astroquartz II and III (pure silica quartz fabric) Astroquartz
SiO2 (99.99% pure fused silica, amorphous), woven continuous fibre
Astroquartz is the trade name for woven fabric and yarn of 99.99% pure fused silica, made by JPS Industries.
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Strength
6 GPa
Stiffness
72 GPa
Low dielectric loss
3.70 at 1 MHz
Heat
1700 °C softening point
Recipe, share of the weight
- Si 46.7%Silicon
- O 53.3%Oxygen
Best for
Radomes and low-dielectric composite reinforcement: a density of 2.2 g/cm3 and a dielectric constant of 3.70 at 1 MHz, as printed by JPS
Weakest at
Evidence depth: the figures come from one manufacturer's data book, most carry no test standard, and no space-exposure or hazard record was found
Risk at a glance
- People Low. Not CLP-classified; SDS prints irritant and dust cautions
- If it fails Moderate. Devitrification of fused silica at high temperature (generic fused quartz, not Astroquartz-specific)
- Corrosion Moderate. Goodfellow rates fused silica 'Fair' against alkalis and against metals.
Quick facts: Astroquartz
| Property | Value | Basis |
|---|---|---|
| Density | 2.2 g/cm³ | 1 sourced value |
| Tensile strength | 3,600 to 6,000 MPa | 2 sourced values across conditions |
| Young's modulus | 72 GPa | 1 sourced value |
| Thermal conductivity | 1.38 W/(m·K) | 1 sourced value |
| Thermal expansion (CTE) | 0.54 ppm/K | 1 sourced value |
What is the density of Astroquartz II and III?
Astroquartz II and III has a density of 2.2 g/cm³. The source and test conditions are listed in the properties table on this page.
What is the thermal conductivity of Astroquartz II and III?
Astroquartz II and III has a thermal conductivity of 1.38 W/(m·K). The source and test conditions are listed in the properties table on this page.
What is the coefficient of thermal expansion of Astroquartz II and III?
Astroquartz II and III has a coefficient of thermal expansion of 0.54 ppm/K. The source and test conditions are listed in the properties table on this page.
What is the tensile strength of Astroquartz II and III?
Astroquartz II and III has a tensile strength of 3,600 to 6,000 MPa. The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the Young's modulus of Astroquartz II and III?
Astroquartz II and III has a Young's modulus of 72 GPa. The source and test conditions are listed in the properties table on this page.
What is Astroquartz II and III used for?
Uses recorded in the sources include Chopped fibre in reinforced plastics, moulding compounds and ceramic composites; Radomes and supporting composite structures; Braided yarn insulation for thermocouple wire, coaxial cables and heating elements.
Why it exists
Astroquartz is JPS's name for woven fabric and yarn made from 99.99% pure fused silica. The data book says JPS has been weaving it since 1964 and that it serves manned and unmanned space programs and radomes. Astroquartz has replaced the older Astroquartz grade, and the current fibres are 9 µm (Astroquartz II) and 14 µm (Astroquartz III) in diameter. The data book states that Astroquartz fabrics offer better solutions when high strength, low dielectric loss and high heat resistance are required, and the figures recorded here are the ones it prints for those three needs.
Where it's used
Radomes and composite structures
The data book says Astroquartz is used in manned and unmanned space programs, as stealth supporting materials, and as radomes for signal integrity on commercial airliners.
Heat-resistant reinforcement
Chopped Astroquartz II fibres add thermal resistance and improved ablation to reinforced plastics, moulding compounds and ceramic composites, according to the data book.
Insulation
Braided Astroquartz yarn is used as insulation for thermocouple wire, coaxial cables, space separators, hoop wire and heating elements, according to the data book.
Recipe
SiO2 (99.99% pure fused silica, amorphous), woven continuous fibre
Astroquartz is woven from continuous filaments of pure fused silica, which the JPS data book gives as 99.99% SiO2 exclusive of binder. Fused quartz is made by fusing high-purity silica sand, and the silica it contains is almost pure and amorphous (non-crystalline), per Wikipedia. The data book does not describe JPS's own melting or drawing steps.
| Ingredient | Atoms per unit | Share of the weight | What it does |
|---|---|---|---|
| Silicon Si | 1 | 46.7% | The one silicon atom in each SiO2 unit. Silicon dioxide is the dioxide of silicon, and silica is the major constituent of sand (Wikipedia). |
| Oxygen O | 2 | 53.3% | The two oxygen atoms in each SiO2 unit, matching the chemical formula SiO2 printed on Wikipedia. |
Weight shares are calculated from standard atomic weights.
What it can do
Strength
6 GPa
measured
The data book prints 6.0 GPa (870 ksi) for a virgin single filament and 3.6 GPa (530 ksi) for an impregnated strand on a 20-end roving, tested to ASTM D-2343.
Stiffness
72 GPa
measured
The printed Young's modulus is 72 GPa (10 msi). The data book gives no test standard for this figure.
Low dielectric loss
3.70 at 1 MHz
measured
The data book prints a dielectric constant of 3.70 at 1 MHz and 3.74 at 10 GHz, with dissipation factors of 0.0001 and 0.0002. These sit in the fused quartz electrical block, so they may describe the bulk glass rather than the woven fabric.
Heat
1700 °C softening point
The data book prints a softening point of 1700 ºC (3092 ºF) at a log10 viscosity of 7.6. The metric fibre table gives the same figure as a decomposition temperature, and both labels are kept in the record.
How it compares
In the data book's metric fibre table, Astroquartz (2.20 g/cm3, 6.0 GPa, 72 GPa, 0.54 per °C and decomposition at 1700 °C) is the lightest of the glass fibres listed and has the highest listed decomposition temperature. E-glass is 2.50 g/cm3 with 2.6 GPa, 72 GPa and decomposition at 730 °C. S-2 glass is 2.48 g/cm3 with 4.8 GPa, 85 GPa and decomposition at 850 °C, and its thermal expansion of 0.48 per °C is slightly below the 0.54 printed for Astroquartz. Kevlar 49 and Twaron 1000 are aramids at 1.44 g/cm3 with decomposition at 450 °C. These are one manufacturer's figures, so the comparison holds within that single document only.
The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details.
| Measurement | Astroquartz |
|---|---|
| Thermal behavior and safety | |
| Thermal conductivity | 1.38 W/mK14 |
| Physical and electrical | |
| Density, Astroquartz II and III fibre | 2.2 g/cm³1 |
| Hardness, Mohs scale | 7 -19 |
| Other measurements | |
| Tensile strength, virgin single filament | 6 GPa2 |
| Tensile strength, impregnated strand on 20-end roving | 3.6 GPa3 |
| Young's modulus, Astroquartz fibre | 72 GPa4 |
| Poisson's ratio, Astroquartz fibre | 0.16 -5 |
| Silica content, exclusive of yarn binder | 99.99 %6 |
| Fibre diameter, Astroquartz II | 9 µm7 |
| Fibre diameter, Astroquartz III | 14 µm8 |
| Dielectric constant at 1 MHz | 3.7 -9 |
| Dielectric constant at 10 GHz | 3.74 -10 |
| Dissipation factor at 1 MHz | 1×10^-4 -11 |
| Dissipation factor at 10 GHz | 2×10^-4 -12 |
| Linear expansion coefficient | 0.54 10-6/°C13 |
| Strain point | 1070 °C15 |
| Annealing point | 1220 °C16 |
| Softening point | 1700 °C17 |
| Refractive index | 1.458 -18 |
| Field of transparency | 0.2 to 4 µm20 |
Why choose it, and why not
Good for
- Low-dielectric radome and composite reinforcement: a dielectric constant of 3.70 at 1 MHz, as printed by JPS.
- Strength and stiffness: a 6.0 GPa virgin single-filament strength and a 72 GPa Young's modulus, as printed.
- Thermal insulation: braided yarn for thermocouple wire and coaxial cables, as described by JPS.
Watch out for
- One manufacturer's data book is the only source for the mechanical and electrical figures, and most of them carry no test standard.
- The 1700 ºC figure is labelled a softening point in one table and a decomposition temperature in another.
- The product page summary gives 0.5 MSI for the roving fibre strength, which differs from the data book's 3.6 GPa (530 ksi) impregnated strand value.
- No outgassing, atomic oxygen, radiation or UV test for Astroquartz was found, so durability in space is not established by our sources.
Astroquartz is a pure silica fibre fabric with a data-book density of 2.2 g/cm3, a virgin single-filament strength of 6.0 GPa and a dielectric constant of 3.70 at 1 MHz. Its figures come from one manufacturer. Corrosion, hazard, supply and space-exposure data are missing and listed as gaps.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Density, Astroquartz II and III fibre | Printed as 2.2 g/cm3 in the Properties of Astroquartz Fibers list; no test standard printed | form pure silica fibre, Astroquartz II and IIIbasis value as printed in the fibre properties list | The metric fibre table prints 2.20 g/cm3 for Astroquartz, and lists E-glass at 2.50 g/cm3, S-2 glass at 2.48 g/cm3 and Twaron 1000 at 1.44 g/cm3 for comparison. |
| 2 | Tensile strength, virgin single filament | Printed as 6.0 GPa (870 ksi) in the Properties of Astroquartz Fibers list | form virgin single filamenttest not stated in the data book | The metric fibre table lists E-glass at 2.6 GPa, S-2 glass at 4.8 GPa, Kevlar 49 at 2.9 GPa and Twaron 1000 at 3.5 GPa for comparison. |
| 3 | Tensile strength, impregnated strand on 20-end roving | Printed as 3.6 GPa (530 ksi) in the Properties of Astroquartz Fibers list, tested to ASTM D-2343 | form impregnated strand on 20-end rovingtest ASTM D-2343 | The product page lists a different roving fibre tensile strength (0.5 MSI); the data book value is the one recorded here. |
| 4 | Young's modulus, Astroquartz fibre | Printed as 72 GPa (10 msi) in the Properties of Astroquartz Fibers list | form fibretest not stated in the data book | The metric fibre table lists E-glass at 72 GPa, S-2 glass at 85 GPa, Kevlar 49 at 109 GPa and Twaron 1000 at 65 GPa. |
| 5 | Poisson's ratio, Astroquartz fibre | Printed as 0.16 in the Properties of Astroquartz Fibers list | form fibretest not stated in the data book | — |
| 6 | Silica content, exclusive of yarn binder | Printed as 99.99% in the Properties of Astroquartz Fibers list; the Astroquartz II chopped fibre and yarn sections print the same 99.99% SiO2 | basis exclusive of yarn binderproduct Astroquartz II and III | — |
| 7 | Fibre diameter, Astroquartz II | Printed as 9µm in the Properties of Astroquartz Fibers list | grade Astroquartz II | — |
| 8 | Fibre diameter, Astroquartz III | Printed as 14µm in the Properties of Astroquartz Fibers list | grade Astroquartz III | — |
| 9 | Dielectric constant at 1 MHz | Printed as 3.70 at 1 MHz in the Physical Properties of Fused Quartz, Electrical Properties block; the Astroquartz product page also prints 3.7 at 1 MHz | frequency 1 MHzbasis listed in the Electrical Properties block of the fused quartz table that the data book applies to Astroquartz | The block is headed fused quartz, so the value may describe the bulk glass rather than a woven fabric. No fabric or laminate dielectric constant was found. |
| 10 | Dielectric constant at 10 GHz | Printed as 3.74 at 10 GHz in the Physical Properties of Fused Quartz, Electrical Properties block | frequency 10 GHzbasis fused quartz electrical block, as above | — |
| 11 | Dissipation factor at 1 MHz | Printed as 0.0001 at 1 MHz (Dissipation Factor, Df) in the Electrical Properties block | frequency 1 MHzbasis fused quartz electrical block, as above | — |
| 12 | Dissipation factor at 10 GHz | Printed as 0.0002 at 10 GHz (Dissipation Factor, Df) in the Electrical Properties block | frequency 10 GHzbasis fused quartz electrical block, as above | — |
| 13 | Linear expansion coefficient | Printed as 0.54 x 10-6 per ºC (the exponent is a superscript in the table); the metric fibre table prints 0.54 for Astroquartz | temperature not stated; single value as printedbasis linear expansion, fused quartz Thermal Properties block | The metric fibre table lists E-glass at 1.60 with decomposition at 730 ºC, S-2 glass at 0.48 with decomposition at 850 ºC, and Kevlar 49 at -2.70 with decomposition at 450 ºC. |
| 14 | Thermal conductivity | Printed as 1.38 W/mK in the Physical Properties of Fused Quartz, Thermal Properties block | temperature not statedbasis fused quartz Thermal Properties block, as above | — |
| 15 | Strain point | Printed as 1070ºC (1958ºF) at Log 10 n = 14.6 in the Thermal Properties block | viscosity log10 n = 14.6, n in poisebasis fused quartz Thermal Properties block | — |
| 16 | Annealing point | Printed as 1220ºC (2084ºF) at Log10 n = 13 in the Thermal Properties block | viscosity log10 n = 13, n in poisebasis fused quartz Thermal Properties block | — |
| 17 | Softening point | Printed as 1700ºC (3092ºF) at Log10 n = 7.6 as softening point; the metric fibre table prints 1700 ºC for Astroquartz under decomposition temperature | viscosity log10 n = 7.6, n in poisebasis fused quartz Thermal Properties block | The same book uses two labels for the 1700 ºC figure. Both are recorded as printed and not reconciled. |
| 18 | Refractive index | Printed as 1.4585 at 15ºC in the Optical Properties block | temperature 15 ºC as printedbasis fused quartz Optical Properties block | — |
| 19 | Hardness, Mohs scale | Printed as 7 on the Mohs scale in the Mechanical Properties block | scale Mohsbasis fused quartz Mechanical Properties block | — |
| 20 | Field of transparency | Printed as 0.2 to 4.0 µm in the Field of Transparency line of the Optical Properties block | basis fused quartz Optical Properties block | — |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Concentrated and dilute acids, and halogens (Goodfellow fused silica sheet) | low | Goodfellow rates fused silica 'Good' against concentrated acids, dilute acids and halogens.1 |
| Alkalis and metals (Goodfellow fused silica sheet) | moderate | Goodfellow rates fused silica 'Fair' against alkalis and against metals.2 |
| Strong acids and strong alkali (Washington Mills fused silica SDS) | not rated | The Washington Mills SDS says the fused silica 'Reacts with strong acids and alkali'.3 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Concentrated and dilute acids, and halogens (Goodfellow fused silica sheet) | The Goodfellow chemical resistance table prints Acids - concentrated 'Good', Acids - dilute 'Good' and Halogens 'Good'. The table is for Goodfellow's fused silica sheet, not for Astroquartz, and it gives no test conditions. | product Goodfellow fused silica sheet, product code SI82-SH-000163test not stated on the product page |
| 2 | Alkalis and metals (Goodfellow fused silica sheet) | The same table prints Alkalis 'Fair' and Metals 'Fair'. The rating is qualitative, and the table is for the sheet product, not Astroquartz. | product Goodfellow fused silica sheet, product code SI82-SH-000163test not stated on the product page |
| 3 | Strong acids and strong alkali (Washington Mills fused silica SDS) | Section 10.3 prints 'Reacts with strong acids and alkali. Reacts with strong oxidising agents.' This conflicts with the Goodfellow table, which rates concentrated acids 'Good'. Both are recorded and not reconciled, and neither source tests Astroquartz. | product Washington Mills fused silica, CAS 7631-86-9test no test conditions printed |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
No safety data sheet for Astroquartz itself was found. A Washington Mills safety data sheet for generic fused silica is not classified as hazardous under CLP or OSHA GHS, but it prints slight irritant effects and dust cautions. It is not an Astroquartz SDS.
- Dust
- The SDS says 'Prevent formation of dust.' and 'Do not inhale dust / smoke / mist.' Check the Astroquartz supplier's safety data sheet before cutting or sanding.
- Handling
- The data book describes a binder-removal heat step and says the mat can be cut to size.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Devitrification of fused silica at high temperature (generic fused quartz, not Astroquartz-specific)moderate severity | Long exposure at high temperature; the page says the transformation to beta-cristobalite generally does not occur below 1000 °CCristobalite nucleates only at the free surface, and surface contamination by alkali elements starts nucleation. The page says the devitrification rate increases with increasing hydroxyl (OH) content, decreasing viscosity and increasing temperature. |
| Spalling from thermal cycling through the cristobalite inversion (generic fused quartz)moderate severity | Thermal cycling through the crystallographic inversion temperature range, around 270 °CThe inversion is accompanied by a large change in density and can result in spalling and possible mechanical failure. |
Handling and storage
- Mat binder: the Astroquartz mat holds 4% to 5% of a polyvinyl alcohol binder by weight. The binder can be removed by heating to 900ºF for 1 hour, or at 500ºF for 24 hours.
- The mat can be cut or fabricated to exact dimensions, and cut sheets of about 500 mm by 500 mm (20 in by 20 in) are available.
Supply and geography
How common the raw materials are and where they come from.
Silicon metal, the element in silica (no fused silica or Astroquartz production shares are printed in any source we hold)
The USGS silicon chapter prints no crustal abundance figure. Its World Resources note says: 'The source of the silicon is silica in various natural forms, such as quartzite.'
- Top producers (2025)
- China 87%, Brazil 3.9%, Norway 2.8%, France 1.5%
- Critical mineral lists
- US: listed
- Recycling
- USGS silicon chapter: 'Recycling: Insignificant.'
Astroquartz fabric and yarn (manufacturer location)
- Top producers
- United States, Anderson, South Carolina (JPS Composite Materials)
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
Show the full YAML
spore: profile
id: astroquartz
spore_version: 0.2
family: silica-fibre
name: Astroquartz II and III (pure silica quartz fabric)
abbreviation: Astroquartz
role: Woven fabric and yarn of 99.99% pure fused silica for radomes, composite reinforcement and high-temperature insulation
category: textiles
type: beta-cloth
summary: |
Astroquartz is the trade name for woven fabric and yarn of 99.99% pure fused silica, made by JPS Industries. JPS says it has been weaving the fabric since 1964 and that it is used in manned and unmanned space programs and as radomes. The JPS data book gives a virgin single-filament tensile strength of 6.0 GPa (870 ksi), a Young's modulus of 72 GPa (10 msi), a density of 2.2 g/cm3 and a dielectric constant of 3.70 at 1 MHz. The softening point is printed as 1700 ºC (3092 ºF).
best_for: 'Radomes and low-dielectric composite reinforcement: a density of 2.2 g/cm3 and a dielectric constant of 3.70 at 1 MHz, as printed by JPS'
weakest_at: 'Evidence depth: the figures come from one manufacturer''s data book, most carry no test standard, and no space-exposure or hazard record was found'
identity:
formula: SiO2 (99.99% pure fused silica, amorphous), woven continuous fibre
source: jps-databook-2017
where: Astroquartz II and III Properties (book p. 37), Silica Content 99.99% exclusive of yarn binder; amorphous form per the Wikipedia Fused quartz lead
tags:
environments: []
stresses: []
applications:
- structures
- heat-shields
- electronics-and-chips
properties:
- benchmark: density
label: Density, Astroquartz II and III fibre
value: 2.2
unit: g/cm3
scope: material
conditions:
form: pure silica fibre, Astroquartz II and III
basis: value as printed in the fibre properties list
method: Printed as 2.2 g/cm3 in the Properties of Astroquartz Fibers list; no test standard printed
status: ground
note: The metric fibre table prints 2.20 g/cm3 for Astroquartz, and lists E-glass at 2.50 g/cm3, S-2 glass at 2.48 g/cm3 and Twaron 1000 at 1.44 g/cm3 for comparison.
source: jps-databook-2017
where: Astroquartz II and III Properties, Properties of Astroquartz Fibers (book p. 37); Technical References, Metric fibre table
- benchmark: ultimate_tensile_strength
label: Tensile strength, virgin single filament
value: 6
unit: GPa
scope: material
conditions:
form: virgin single filament
test: not stated in the data book
method: Printed as 6.0 GPa (870 ksi) in the Properties of Astroquartz Fibers list
status: ground
note: The metric fibre table lists E-glass at 2.6 GPa, S-2 glass at 4.8 GPa, Kevlar 49 at 2.9 GPa and Twaron 1000 at 3.5 GPa for comparison.
source: jps-databook-2017
where: Astroquartz II and III Properties, Properties of Astroquartz Fibers (book p. 37); Technical References, Metric fibre table
- benchmark: ultimate_tensile_strength
label: Tensile strength, impregnated strand on 20-end roving
value: 3.6
unit: GPa
scope: material
conditions:
form: impregnated strand on 20-end roving
test: ASTM D-2343
method: Printed as 3.6 GPa (530 ksi) in the Properties of Astroquartz Fibers list, tested to ASTM D-2343
status: ground
note: The product page lists a different roving fibre tensile strength (0.5 MSI); the data book value is the one recorded here.
source: jps-databook-2017
where: Astroquartz II and III Properties, Properties of Astroquartz Fibers (book p. 37)
- benchmark: elastic_modulus
label: Young's modulus, Astroquartz fibre
value: 72
unit: GPa
scope: material
conditions:
form: fibre
test: not stated in the data book
method: Printed as 72 GPa (10 msi) in the Properties of Astroquartz Fibers list
status: ground
note: The metric fibre table lists E-glass at 72 GPa, S-2 glass at 85 GPa, Kevlar 49 at 109 GPa and Twaron 1000 at 65 GPa.
source: jps-databook-2017
where: Astroquartz II and III Properties, Properties of Astroquartz Fibers (book p. 37); Technical References, Metric fibre table
- benchmark: poissons_ratio
label: Poisson's ratio, Astroquartz fibre
value: 0.16
unit: '-'
scope: material
conditions:
form: fibre
test: not stated in the data book
method: Printed as 0.16 in the Properties of Astroquartz Fibers list
status: ground
source: jps-databook-2017
where: Astroquartz II and III Properties, Properties of Astroquartz Fibers (book p. 37)
- benchmark: silica_content
label: Silica content, exclusive of yarn binder
value: 99.99
unit: '%'
scope: material
conditions:
basis: exclusive of yarn binder
product: Astroquartz II and III
method: Printed as 99.99% in the Properties of Astroquartz Fibers list; the Astroquartz II chopped fibre and yarn sections print the same 99.99% SiO2
status: ground
source: jps-databook-2017
where: Astroquartz II and III Properties, Properties of Astroquartz Fibers (book p. 37); Astroquartz II Chopped Fiber and Astroquartz Yarn sections
- benchmark: fiber_diameter
label: Fibre diameter, Astroquartz II
value: 9
unit: µm
scope: material
conditions:
grade: Astroquartz II
method: Printed as 9µm in the Properties of Astroquartz Fibers list
status: ground
source: jps-databook-2017
where: Astroquartz II and III Properties, Properties of Astroquartz Fibers (book p. 37)
- benchmark: fiber_diameter
label: Fibre diameter, Astroquartz III
value: 14
unit: µm
scope: material
conditions:
grade: Astroquartz III
method: Printed as 14µm in the Properties of Astroquartz Fibers list
status: ground
source: jps-databook-2017
where: Astroquartz II and III Properties, Properties of Astroquartz Fibers (book p. 37)
- benchmark: dielectric_constant
label: Dielectric constant at 1 MHz
value: 3.7
unit: '-'
scope: material
conditions:
frequency: 1 MHz
basis: listed in the Electrical Properties block of the fused quartz table that the data book applies to Astroquartz
method: Printed as 3.70 at 1 MHz in the Physical Properties of Fused Quartz, Electrical Properties block; the Astroquartz product page also prints 3.7 at 1 MHz
status: ground
note: The block is headed fused quartz, so the value may describe the bulk glass rather than a woven fabric. No fabric or laminate dielectric constant was found.
source: jps-databook-2017
where: Physical Properties of Fused Quartz, Electrical Properties (book p. 38)
- benchmark: dielectric_constant
label: Dielectric constant at 10 GHz
value: 3.74
unit: '-'
scope: material
conditions:
frequency: 10 GHz
basis: fused quartz electrical block, as above
method: Printed as 3.74 at 10 GHz in the Physical Properties of Fused Quartz, Electrical Properties block
status: ground
source: jps-databook-2017
where: Physical Properties of Fused Quartz, Electrical Properties (book p. 38)
- benchmark: dissipation_factor
label: Dissipation factor at 1 MHz
value: 0.0001
unit: '-'
scope: material
conditions:
frequency: 1 MHz
basis: fused quartz electrical block, as above
method: Printed as 0.0001 at 1 MHz (Dissipation Factor, Df) in the Electrical Properties block
status: ground
source: jps-databook-2017
where: Physical Properties of Fused Quartz, Electrical Properties (book p. 38)
- benchmark: dissipation_factor
label: Dissipation factor at 10 GHz
value: 0.0002
unit: '-'
scope: material
conditions:
frequency: 10 GHz
basis: fused quartz electrical block, as above
method: Printed as 0.0002 at 10 GHz (Dissipation Factor, Df) in the Electrical Properties block
status: ground
source: jps-databook-2017
where: Physical Properties of Fused Quartz, Electrical Properties (book p. 38)
- benchmark: cte
label: Linear expansion coefficient
value: 0.54
unit: 10-6/°C
scope: material
conditions:
temperature: not stated; single value as printed
basis: linear expansion, fused quartz Thermal Properties block
method: Printed as 0.54 x 10-6 per ºC (the exponent is a superscript in the table); the metric fibre table prints 0.54 for Astroquartz
status: ground
note: The metric fibre table lists E-glass at 1.60 with decomposition at 730 ºC, S-2 glass at 0.48 with decomposition at 850 ºC, and Kevlar 49 at -2.70 with decomposition at 450 ºC.
source: jps-databook-2017
where: Physical Properties of Fused Quartz, Thermal Properties (book p. 38); Technical References, Metric fibre table
- benchmark: thermal_conductivity
label: Thermal conductivity
value: 1.38
unit: W/mK
scope: material
conditions:
temperature: not stated
basis: fused quartz Thermal Properties block, as above
method: Printed as 1.38 W/mK in the Physical Properties of Fused Quartz, Thermal Properties block
status: ground
source: jps-databook-2017
where: Physical Properties of Fused Quartz, Thermal Properties (book p. 38)
- benchmark: strain_point
label: Strain point
value: 1070
unit: °C
scope: material
conditions:
viscosity: log10 n = 14.6, n in poise
basis: fused quartz Thermal Properties block
method: Printed as 1070ºC (1958ºF) at Log 10 n = 14.6 in the Thermal Properties block
status: ground
source: jps-databook-2017
where: Physical Properties of Fused Quartz, Thermal Properties (book p. 38)
- benchmark: annealing_point
label: Annealing point
value: 1220
unit: °C
scope: material
conditions:
viscosity: log10 n = 13, n in poise
basis: fused quartz Thermal Properties block
method: Printed as 1220ºC (2084ºF) at Log10 n = 13 in the Thermal Properties block
status: ground
source: jps-databook-2017
where: Physical Properties of Fused Quartz, Thermal Properties (book p. 38)
- benchmark: softening_point
label: Softening point
value: 1700
unit: °C
scope: material
conditions:
viscosity: log10 n = 7.6, n in poise
basis: fused quartz Thermal Properties block
method: Printed as 1700ºC (3092ºF) at Log10 n = 7.6 as softening point; the metric fibre table prints 1700 ºC for Astroquartz under decomposition temperature
status: ground
note: The same book uses two labels for the 1700 ºC figure. Both are recorded as printed and not reconciled.
source: jps-databook-2017
where: Physical Properties of Fused Quartz, Thermal Properties (book p. 38); Technical References, Metric fibre table
- benchmark: refractive_index
label: Refractive index
value: 1.4585
unit: '-'
scope: material
conditions:
temperature: 15 ºC as printed
basis: fused quartz Optical Properties block
method: Printed as 1.4585 at 15ºC in the Optical Properties block
status: ground
source: jps-databook-2017
where: Physical Properties of Fused Quartz, Optical Properties (book p. 38)
- benchmark: mohs_hardness
label: Hardness, Mohs scale
value: 7
unit: '-'
scope: material
conditions:
scale: Mohs
basis: fused quartz Mechanical Properties block
method: Printed as 7 on the Mohs scale in the Mechanical Properties block
status: ground
source: jps-databook-2017
where: Physical Properties of Fused Quartz, Mechanical Properties (book p. 38)
- benchmark: transmission_range
label: Field of transparency
value: 0.2
value_high: 4
bound: range
unit: µm
scope: material
conditions:
basis: fused quartz Optical Properties block
method: Printed as 0.2 to 4.0 µm in the Field of Transparency line of the Optical Properties block
status: ground
source: jps-databook-2017
where: Physical Properties of Fused Quartz, Optical Properties (book p. 38)
corrosion:
- environment: Concentrated and dilute acids, and halogens (Goodfellow fused silica sheet)
headline: Goodfellow rates fused silica 'Good' against concentrated acids, dilute acids and halogens.
effect: The Goodfellow chemical resistance table prints Acids - concentrated 'Good', Acids - dilute 'Good' and Halogens 'Good'. The table is for Goodfellow's fused silica sheet, not for Astroquartz, and it gives no test conditions.
rating: low
conditions:
product: Goodfellow fused silica sheet, product code SI82-SH-000163
test: not stated on the product page
source: goodfellow-fused-silica
where: Chemical Resistance table, product page
- environment: Alkalis and metals (Goodfellow fused silica sheet)
headline: Goodfellow rates fused silica 'Fair' against alkalis and against metals.
effect: The same table prints Alkalis 'Fair' and Metals 'Fair'. The rating is qualitative, and the table is for the sheet product, not Astroquartz.
rating: moderate
conditions:
product: Goodfellow fused silica sheet, product code SI82-SH-000163
test: not stated on the product page
source: goodfellow-fused-silica
where: Chemical Resistance table, product page
- environment: Strong acids and strong alkali (Washington Mills fused silica SDS)
headline: The Washington Mills SDS says the fused silica 'Reacts with strong acids and alkali'.
effect: Section 10.3 prints 'Reacts with strong acids and alkali. Reacts with strong oxidising agents.' This conflicts with the Goodfellow table, which rates concentrated acids 'Good'. Both are recorded and not reconciled, and neither source tests Astroquartz.
rating: unknown
conditions:
product: Washington Mills fused silica, CAS 7631-86-9
test: no test conditions printed
source: wm-sds
where: Section 10.3, Possibility of Hazardous Reactions
risks:
hazards:
- text: The Washington Mills safety data sheet for generic fused silica (chemical name silicon dioxide, CAS 7631-86-9, revision 08.06.2015; not an Astroquartz SDS) says the substance is not classified as hazardous under CLP and is not classified under OSHA GHS. It lists no hazard statement or pictogram (Not Regulated).
ghs: []
source: wm-sds
where: Sections 2.1 and 2.2, Label Elements
- text: The same SDS prints 'Slight irritant effect on eyes', 'Slight irritant effect on skin and mucous membranes' and 'Dermal LD50 5000 mg/kg (rat)'.
ghs: []
source: wm-sds
where: Section 4.2 (eyes); Section 11, Toxicological Information
- text: The SDS says 'Prevent formation of dust.' and 'Do not inhale dust / smoke / mist.' Section 11 says it 'Contains known or suspect carcinogens when inhaled.' and that the product 'is nonclassifiable as a carcinogen' in non-inhalable form. Its carcinogen categories table gives IARC group 3 for silicon dioxide.
ghs: []
source: wm-sds
where: Sections 7.1, 8 and 11; Carcinogenic Categories table
failure_risks:
- mode: Devitrification of fused silica at high temperature (generic fused quartz, not Astroquartz-specific)
trigger: Long exposure at high temperature; the page says the transformation to beta-cristobalite generally does not occur below 1000 °C
consequence: Cristobalite nucleates only at the free surface, and surface contamination by alkali elements starts nucleation. The page says the devitrification rate increases with increasing hydroxyl (OH) content, decreasing viscosity and increasing temperature.
severity: moderate
source: machinedquartz-thermal
where: Devitrification and Cristobalite Growth sections
- mode: Spalling from thermal cycling through the cristobalite inversion (generic fused quartz)
trigger: Thermal cycling through the crystallographic inversion temperature range, around 270 °C
consequence: The inversion is accompanied by a large change in density and can result in spalling and possible mechanical failure.
severity: moderate
source: machinedquartz-thermal
where: Cristobalite Growth section
side_effects: []
handling:
- text: 'Mat binder: the Astroquartz mat holds 4% to 5% of a polyvinyl alcohol binder by weight. The binder can be removed by heating to 900ºF for 1 hour, or at 500ºF for 24 hours.'
source: jps-databook-2017
where: Astroquartz Mat, Handling section
- text: The mat can be cut or fabricated to exact dimensions, and cut sheets of about 500 mm by 500 mm (20 in by 20 in) are available.
source: jps-databook-2017
where: Astroquartz Mat, Handling section
mitigations: []
uses:
- application: heat-shields
device: Chopped fibre in reinforced plastics, moulding compounds and ceramic composites
example: JPS says chopped Astroquartz II fibres add thermal resistance and improved ablation to the final part.
source: jps-databook-2017
where: Astroquartz II Chopped Fiber section
- application: structures
device: Radomes and supporting composite structures
example: JPS says Astroquartz is used in manned and unmanned space programs, as stealth supporting materials, and as radomes for signal integrity; the book names no specific flight or radome.
source: jps-databook-2017
where: Astroquartz Products page (book p. 36)
- application: electronics-and-chips
device: Braided yarn insulation for thermocouple wire, coaxial cables and heating elements
example: JPS says Astroquartz yarn is widely used in braided insulation for thermocouple wire, coaxial cables, space separators, hoop wire and heating elements.
source: jps-databook-2017
where: Astroquartz Yarn section
supply:
- subject: Silicon metal, the element in silica (no fused silica or Astroquartz production shares are printed in any source we hold)
abundance: 'The USGS silicon chapter prints no crustal abundance figure. Its World Resources note says: ''The source of the silicon is silica in various natural forms, such as quartzite.'''
producers:
- country: China
share_percent: 87
year: 2025
- country: Brazil
share_percent: 3.9
year: 2025
- country: Norway
share_percent: 2.8
year: 2025
- country: France
share_percent: 1.5
year: 2025
critical_lists:
- list: USGS 2025 Final List of Critical Minerals (silicon added in 2025)
listed: true
recycling: 'USGS silicon chapter: ''Recycling: Insignificant.'''
substitutes: []
source: usgs-silicon-2026
where: World Production table, silicon metal, 2025 (thousand metric tons, silicon content). Shares calculated by Space Mushroom from the printed 2025 tonnages against the printed 2025 world total of 4,600; US output is withheld (W) and excluded. Recycling; Critical minerals text.
- subject: Astroquartz fabric and yarn (manufacturer location)
producers:
- country: United States, Anderson, South Carolina (JPS Composite Materials)
source: jps-databook-2017
where: 'Company section, Locations list: Anderson, South Carolina, Aerospace Composite, Astroquartz, Aramid and Specialty Fabrics. The data book prints no production share or year.'
media: []
documents:
- title: 'JPS Industries Astroquartz data book (2017): Astroquartz II and III properties, fused quartz and fibre tables'
type: datasheet
url: https://jpscm.com/wp-content/uploads/2017/10/2017-Data-Book-Small-1.pdf
year: 2017
- title: 'JPS Astroquartz product page: Astroquartz II and III properties'
type: datasheet
url: https://jpscm.com/?p=2911
- title: NIST Atomic Weights and Isotopic Compositions for All Elements (Si and O rows)
type: database
url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=Si&all=all&ascii=html
- title: 'USGS Mineral Commodity Summaries 2026: Silicon'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-silicon.pdf
year: 2026
- title: Washington Mills fused silica (CAS 7631-86-9) safety data sheet, revision 08.06.2015
type: sds
url: https://www.physics.purdue.edu/primelab/safety/MSDS/SDS/Fused%20Quartz%20(Silica)%20-%20Washington%20Mills.pdf
- title: Goodfellow fused silica sheet, product code SI82-SH-000163
type: datasheet
url: https://www.goodfellow.com/usa/fused-silica-sheet-1000002656
- title: Thermal properties of fused quartz, machinedquartz.com
type: datasheet
url: https://machinedquartz.com/?p=9934
gaps:
- No space-environment test for Astroquartz was found (outgassing, atomic oxygen, radiation, UV or thermal cycling). The space-program use is JPS's own statement, and no NASA or ESA source naming an Astroquartz flight was found.
- No Astroquartz-specific safety data sheet was found. The hazard entries use a Washington Mills SDS for generic fused silica (CAS 7631-86-9, revision 08.06.2015). The PubChem record for silicon dioxide could not be read because the site showed a browser verification page.
- The quartz exposure limits in the Washington Mills SDS (CAS 14808-60-7) are for crystalline quartz and are not recorded here.
- No hydrofluoric acid attack was verified from a fetched page. Neither the Washington Mills SDS nor the Goodfellow table names a rating for hydrofluoric acid.
- The corrosion entries use a Goodfellow table for a fused silica sheet and the Washington Mills SDS. Neither tests Astroquartz, and their acid ratings conflict; both are recorded and not reconciled. No moisture or UV ageing figure was found.
- The failure_risks use a machinedquartz.com page for generic fused quartz, which attributes its text to Momentive Performance Materials. No Astroquartz-specific devitrification or thermal-cycling test was found. The severity ratings are the assistant's grading of the consequences the page states.
- The supply silicon entry is silicon metal, the nearest element-level figure in the USGS silicon chapter. No fused silica or Astroquartz production shares are printed in any source we hold. US output is withheld and excluded from the calculated shares.
- The data book prints no production year for Astroquartz manufacture; the location is taken from its Locations list.
- Specific heat is printed as 7.5 x 10 with the unit J/gK; the exponent and the unit do not agree, so the figure is not recorded.
- The data book labels the 1700 ºC figure as a softening point (fused quartz block) and as a decomposition temperature (metric fibre table). Both labels are kept and not reconciled.
- The product page summary gives 0.5 MSI for the Astroquartz II roving fibre tensile strength, while the data book gives 3.6 GPa (530 ksi) for an impregnated strand on a 20-end roving. The data book value is recorded; the 0.5 MSI figure is not.
- The dielectric constant, dissipation factor, thermal conductivity, strain, annealing and softening points, refractive index, Mohs hardness and transparency range are printed in the fused quartz blocks of the data book. No separate woven-fabric or laminate value was found.
- Silica content, fibre diameter, strain point, annealing point, softening point, Mohs hardness and field of transparency use custom names, because property-canon.yaml has no matching canonical name.
- The data book gives no test standard for density, Young's modulus, Poisson's ratio or tensile strength, so their test conditions are recorded as not stated.
- Weave styles, fabric weights and yarn counts are described in the data book but are not recorded here.
- Environment tags are empty because no environment for Astroquartz itself was found in a source. Wikipedia's space-window examples concern fused quartz, not Astroquartz.
- No image was added; no licensed image was checked for this profile.
sources:
jps-databook-2017:
title: JPS Industries Astroquartz data book, 2017 edition (Astroquartz II and III properties, Physical Properties of Fused Quartz, Technical References fibre tables)
id: JPS Industries data book, 2017, PDF
url: https://jpscm.com/wp-content/uploads/2017/10/2017-Data-Book-Small-1.pdf
year: 2017
kind: datasheet
license: manufacturer document, linked not reproduced
jps-product-page:
title: JPS Astroquartz product page (Astroquartz II and III properties and product sections)
id: jpscm.com ?p=2911
url: https://jpscm.com/?p=2911
kind: datasheet
license: manufacturer web page, linked not reproduced
wikipedia-fused-quartz:
title: Fused quartz, Wikipedia
id: Fused quartz article, Composition, Manufacture and Applications sections
url: https://en.wikipedia.org/wiki/Fused_quartz
kind: web
license: CC BY-SA 4.0, linked not reproduced
wikipedia-silicon-dioxide:
title: Silicon dioxide, Wikipedia
id: Silicon dioxide article, lead and Structure sections
url: https://en.wikipedia.org/wiki/Silicon_dioxide
kind: web
license: CC BY-SA 4.0, linked not reproduced
nist-atomic-weights:
title: NIST Atomic Weights and Isotopic Compositions for All Elements (Si and O rows)
id: 'NIST standard atomic weight table: Si [28.084, 28.086]; O [15.999 03, 15.999 77]'
url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=Si&all=all&ascii=html
kind: database
license: US government data
usgs-silicon-2026:
title: 'USGS Mineral Commodity Summaries 2026: Silicon (World Production table, Recycling, Critical minerals text)'
id: mcs2026-silicon.pdf
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-silicon.pdf
year: 2026
kind: report
license: US government work
wm-sds:
title: Washington Mills fused silica (silicon dioxide, CAS 7631-86-9) safety data sheet, revision 08.06.2015
id: Fused Quartz (Silica) - Washington Mills SDS, PDF
url: https://www.physics.purdue.edu/primelab/safety/MSDS/SDS/Fused%20Quartz%20(Silica)%20-%20Washington%20Mills.pdf
kind: datasheet
license: supplier document, linked not reproduced
goodfellow-fused-silica:
title: Goodfellow fused silica sheet, product code SI82-SH-000163 (Chemical Resistance table)
id: Goodfellow product 1000002656
url: https://www.goodfellow.com/usa/fused-silica-sheet-1000002656
kind: datasheet
license: supplier web page, linked not reproduced
machinedquartz-thermal:
title: Thermal properties of fused quartz, machinedquartz.com (Devitrification and Cristobalite Growth sections)
id: machinedquartz.com ?p=9934
url: https://machinedquartz.com/?p=9934
kind: web
license: web page, linked not reproduced
license: CC-BY-4.0
updated: '2026-11-01'
review:
status: draft
method: assistant
checked_values: 20
unreachable: 2
caveats: 4
note: 'Values read by an AI assistant on 2026-11-01 from the JPS data book (2017, PDF text) and the JPS product page. Deepen pass on 2026-11-01 added hazards and supply from a Washington Mills fused silica SDS and the USGS silicon chapter, and corrosion and failure modes from a Goodfellow fused silica sheet page and machinedquartz.com. PubChem returned a browser verification page and the Wikipedia Astroquartz article returned HTTP 404, so neither was read. Caveats: the 1700 ºC figure carries two labels in the book; most mechanical and electrical values carry no test standard; the dielectric values sit in a fused quartz block; the product page roving strength (0.5 MSI) conflicts with the book; the corrosion and hazard records are for generic fused silica, not Astroquartz.'
story:
recipe:
line: Astroquartz is woven from continuous filaments of pure fused silica, which the JPS data book gives as 99.99% SiO2 exclusive of binder. Fused quartz is made by fusing high-purity silica sand, and the silica it contains is almost pure and amorphous (non-crystalline), per Wikipedia. The data book does not describe JPS's own melting or drawing steps.
parts:
- name: Silicon
symbol: Si
atoms: 1
atomic_weight: 28.084
share_note: NIST standard atomic weight, printed interval [28.084, 28.086]
role: The one silicon atom in each SiO2 unit. Silicon dioxide is the dioxide of silicon, and silica is the major constituent of sand (Wikipedia).
- name: Oxygen
symbol: O
atoms: 2
atomic_weight: 15.99903
share_note: NIST standard atomic weight, printed interval [15.999 03, 15.999 77]
role: The two oxygen atoms in each SiO2 unit, matching the chemical formula SiO2 printed on Wikipedia.
risk_groups:
- title: For people
level: 1
verdict: Not CLP-classified; SDS prints irritant and dust cautions
lead: No safety data sheet for Astroquartz itself was found. A Washington Mills safety data sheet for generic fused silica is not classified as hazardous under CLP or OSHA GHS, but it prints slight irritant effects and dust cautions. It is not an Astroquartz SDS.
points:
- label: Dust
line: The SDS says 'Prevent formation of dust.' and 'Do not inhale dust / smoke / mist.' Check the Astroquartz supplier's safety data sheet before cutting or sanding.
- label: Handling
line: The data book describes a binder-removal heat step and says the mat can be cut to size.
why: Astroquartz is JPS's name for woven fabric and yarn made from 99.99% pure fused silica. The data book says JPS has been weaving it since 1964 and that it serves manned and unmanned space programs and radomes. Astroquartz has replaced the older Astroquartz grade, and the current fibres are 9 µm (Astroquartz II) and 14 µm (Astroquartz III) in diameter. The data book states that Astroquartz fabrics offer better solutions when high strength, low dielectric loss and high heat resistance are required, and the figures recorded here are the ones it prints for those three needs.
uses:
- where: Radomes and composite structures
line: The data book says Astroquartz is used in manned and unmanned space programs, as stealth supporting materials, and as radomes for signal integrity on commercial airliners.
- where: Heat-resistant reinforcement
line: Chopped Astroquartz II fibres add thermal resistance and improved ablation to reinforced plastics, moulding compounds and ceramic composites, according to the data book.
- where: Insulation
line: Braided Astroquartz yarn is used as insulation for thermocouple wire, coaxial cables, space separators, hoop wire and heating elements, according to the data book.
can_do:
- label: Strength
benchmark: ultimate_tensile_strength
line: The data book prints 6.0 GPa (870 ksi) for a virgin single filament and 3.6 GPa (530 ksi) for an impregnated strand on a 20-end roving, tested to ASTM D-2343.
- label: Stiffness
benchmark: elastic_modulus
value: 72 GPa
line: The printed Young's modulus is 72 GPa (10 msi). The data book gives no test standard for this figure.
- label: Low dielectric loss
benchmark: dielectric_constant
value: 3.70 at 1 MHz
line: The data book prints a dielectric constant of 3.70 at 1 MHz and 3.74 at 10 GHz, with dissipation factors of 0.0001 and 0.0002. These sit in the fused quartz electrical block, so they may describe the bulk glass rather than the woven fabric.
- label: Heat
value: 1700 °C softening point
line: The data book prints a softening point of 1700 ºC (3092 ºF) at a log10 viscosity of 7.6. The metric fibre table gives the same figure as a decomposition temperature, and both labels are kept in the record.
compare: In the data book's metric fibre table, Astroquartz (2.20 g/cm3, 6.0 GPa, 72 GPa, 0.54 per °C and decomposition at 1700 °C) is the lightest of the glass fibres listed and has the highest listed decomposition temperature. E-glass is 2.50 g/cm3 with 2.6 GPa, 72 GPa and decomposition at 730 °C. S-2 glass is 2.48 g/cm3 with 4.8 GPa, 85 GPa and decomposition at 850 °C, and its thermal expansion of 0.48 per °C is slightly below the 0.54 printed for Astroquartz. Kevlar 49 and Twaron 1000 are aramids at 1.44 g/cm3 with decomposition at 450 °C. These are one manufacturer's figures, so the comparison holds within that single document only.
compare_rows:
- label: Density
benchmark: density
- label: Tensile strength, virgin single filament
benchmark: ultimate_tensile_strength
- label: Linear expansion
benchmark: cte
handling:
- To remove the 4% to 5% polyvinyl alcohol binder from the mat, heat it to 900 ºF for 1 hour, or to 500 ºF for 24 hours (data book).
- The mat can be cut or fabricated to exact dimensions, and cut sheets of about 500 mm by 500 mm are available (data book).
- The data book gives no hazard or dust data for the fabric, so check the supplier's safety data sheet before cutting or sanding.
good_for:
- 'Low-dielectric radome and composite reinforcement: a dielectric constant of 3.70 at 1 MHz, as printed by JPS.'
- 'Strength and stiffness: a 6.0 GPa virgin single-filament strength and a 72 GPa Young''s modulus, as printed.'
- 'Thermal insulation: braided yarn for thermocouple wire and coaxial cables, as described by JPS.'
watch_out:
- One manufacturer's data book is the only source for the mechanical and electrical figures, and most of them carry no test standard.
- The 1700 ºC figure is labelled a softening point in one table and a decomposition temperature in another.
- The product page summary gives 0.5 MSI for the roving fibre strength, which differs from the data book's 3.6 GPa (530 ksi) impregnated strand value.
- No outgassing, atomic oxygen, radiation or UV test for Astroquartz was found, so durability in space is not established by our sources.
verdict: Astroquartz is a pure silica fibre fabric with a data-book density of 2.2 g/cm3, a virgin single-filament strength of 6.0 GPa and a dielectric constant of 3.70 at 1 MHz. Its figures come from one manufacturer. Corrosion, hazard, supply and space-exposure data are missing and listed as gaps.
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
Updated