Silica Aerogel HD
Supply condition
HD = high-density / ambient-pressure-dried strengthened aerogel
Pick when a rigid, machinable, load-bearing aerogel board is required and a slightly higher conductivity is acceptable.
Values for the HD condition
Other Silica Aerogel tempers and conditions
Silica Aerogel is listed in 5 conditions; see the grade overview at Silica Aerogel.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
MONODefault Supercritically dried monolithic silica aerogel | Classic transparent/translucent block aerogel — pick for optical, Cherenkov-radiator, research and transparent-insulation uses. | — | 0.02 | — | — | 0.02 W/m·K |
Hydrophobic granules / beads | Pick for cavity fill, translucent daylighting panels, coatings and plaster additives where a pourable powder/bead form is needed. | — | 0.03 | — | — | 0.02 W/m·K |
Fiber-reinforced hydrophobic aerogel blanket/felt | Standard industrial form: flexible, cuttable, hydrophobic fiber-reinforced felt — pick for pipe, vessel, LNG and building insulation up to 650 °C where the wrap must follow complex shapes. | — | 0.25 | 5 | — | 0.02 W/m·K |
HDThis page High-density / ambient-pressure-dried strengthened aerogel | Pick when a rigid, machinable, load-bearing aerogel board is required and a slightly higher conductivity is acceptable. | — | 0.5 | 1 | 3 HV | 0.03 W/m·K |
Ultra-low-density monolith | Pick for hypervelocity particle capture, Cherenkov radiators and lowest-possible conductivity research; mechanically almost unhandleable. | — | — | 0.5 | — | 0.01 W/m·K |
What is Silica Aerogel HD?
Silica Aerogel HD is Silica Aerogel supplied in the HD condition — pick when a rigid, machinable, load-bearing aerogel board is required and a slightly higher conductivity is acceptable. Silica Aerogel HD has a tensile strength of 0.5 MPa (0.0725 ksi), weaker than 97% of ceramic grades. The elastic modulus is 0.08 GPa (0.0116 Msi). Silica Aerogel HD has a density of 0.28 g/cm³ (0.0101 lb/in³), lighter than 98% of ceramic grades. MONO is the default condition FabDigit quotes; HD is available on request or by drawing note.
Advantages
- Lightweight — 0.28 g/cm³ (0.0101 lb/in³), better than 98% of ceramic grades
- Easy to machine — 30/100, better than 85% of ceramic grades
Limitations
- Low stiffness — 0.08 GPa (0.0116 Msi), worse than 99% of ceramic grades
- Poor heat conductor — 0.03 W/m·K (0.015 BTU/hr·ft·°F), worse than 99% of ceramic grades
Silica Aerogel HD properties
Typical room-temperature values for Silica Aerogel HD; 14 are specific to this condition. Other listed values are Silica Aerogel reference data and may not represent this condition. Bars are the position among ceramic grades.
Physical4
Silica Aerogel HD has a density of 0.28 g/cm³ (0.0101 lb/in³), lighter than 98% of ceramic grades.
Mechanical7
Silica Aerogel HD has a tensile strength of 0.5 MPa (0.0725 ksi), weaker than 97% of ceramic grades. The elastic modulus is 0.08 GPa (0.0116 Msi).
Thermal5
Silica Aerogel HD is rated for continuous service to 600°C (1,112 °F). It conducts heat at 0.03 W/m·K (0.015 BTU/hr·ft·°F), worse than 99% of ceramic grades. Thermal expansion is 3 µm/m·K (1.67 µin/in·°F).
Electrical4
Silica Aerogel HD has an electrical resistivity of 1×10¹² Ω·m.
Chemical & Environmental2
Corrosion resistance is very good (78/100), better than 53% of ceramic grades.
Sustainability4
Producing a kilogram of Silica Aerogel HD takes about 100 MJ of energy and emits 6 kg of CO₂ — less than 55% of ceramic grades. Typical recycled content is 0%.
Manufacturability2
Silica Aerogel HD's machinability is poor (30/100, better than 85% of ceramic grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Silica Aerogel HD
Is Silica Aerogel easy to machine?
Monoliths are extremely friable — cut dry with a fresh razor/hot wire or low-force diamond wire, never with coolant; blankets and boards are cut with a knife or die, always with dust extraction and PPE.
Can Silica Aerogel be welded?
Not weldable or brazeable; assemble by encapsulation in foil/film jackets, mechanical clamping or silicone/aerogel-compatible adhesives.
Can Silica Aerogel be formed, bent or molded?
Net-shape cast in a mould during sol-gel gelation, then solvent-exchanged and supercritical-CO₂ (or ambient-pressure silylated) dried; blankets are made by gelling around a fiber batt and drying continuously.
What surface finishes work on Silica Aerogel?
Surface silylation (HMDS/TMCS) gives permanent hydrophobicity; edges are sealed or the part encapsulated in PET/aluminium-foil laminates to stop dusting and moisture ingress; no polishing or coating in the conventional sense.
Silica Aerogel 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 |
|---|---|---|
| C (surface -CH3 / silylation)TMCS/HMDS-derived methyl groups on hydrophobic grades; absent in hydrophilic monoliths | 0 – 8 | 4 |
| glass fiber / ceramic fiber0 % in monoliths; 20–40 % in blanket/felt variants | 0 – 40 | 0 |
| opacifier (TiO2, SiC, carbon black)added in high-temperature grades to suppress radiative transfer | 0 – 10 | 0 |
| SiO2amorphous nanoparticle skeleton from waterglass or TEOS/TMOS sol-gel route | ≥ 90 (balance) | — |
Silica Aerogel HD — frequently asked
What is Silica Aerogel HD used for?
Silica Aerogel HD is typically used for thermal insulation blankets, spacecraft/cryogenic insulation, particle detector Cherenkov radiators and aerospace insulation panels. In short: lowest-conductivity solid insulation; density near 0.1 g/cm³; extremely fragile monoliths.
What is the tensile strength of Silica Aerogel HD?
Silica Aerogel HD has a typical tensile strength of 0.5 MPa (0.0725 ksi) — weaker than 97% of ceramic grades. Strength varies by condition: see the 5 listed tempers.
Is Silica Aerogel HD easy to machine?
Not especially — machinability is rated poor (30/100, better than 85% of ceramic grades). Monoliths are extremely friable — cut dry with a fresh razor/hot wire or low-force diamond wire, never with coolant; blankets and boards are cut with a knife or die, always with dust extraction and PPE.
Can Silica Aerogel HD be welded?
Not weldable or brazeable; assemble by encapsulation in foil/film jackets, mechanical clamping or silicone/aerogel-compatible adhesives.
What surface finishes work on Silica Aerogel HD?
Surface silylation (HMDS/TMCS) gives permanent hydrophobicity; edges are sealed or the part encapsulated in PET/aluminium-foil laminates to stop dusting and moisture ingress; no polishing or coating in the conventional sense.
Can Silica Aerogel HD be formed, bent or molded?
Net-shape cast in a mould during sol-gel gelation, then solvent-exchanged and supercritical-CO₂ (or ambient-pressure silylated) dried; blankets are made by gelling around a fiber batt and drying continuously.
What is the maximum service temperature of Silica Aerogel HD?
Silica Aerogel HD is rated for continuous use to about 600°C (1,112 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- Aerogels Handbook (Aegerter, Leventis, Koebel) — Springer (2011)
- ASM Engineered Materials Handbook — Ceramics and Glasses — ASM International (1991)
- Pyrogel / Cryogel aerogel blanket technical data — Aspen Aerogels (2023)
- Enova / Lumira aerogel particle data sheets — Cabot Corporation (2022)
- Monolithic and rigid aerogel property sheets — Aerogel Technologies (2023)
- ASTM C1728 Standard Specification for Flexible Aerogel Insulation — ASTM (2019)
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.