Syntactic Foam (Epoxy) SF-52
Grade
SF-52 = 0.52 g/cm³ ultra-deep buoyancy grade
For hadal-zone floats and instrument housings where 7000–9000 m collapse margin is required.
Values for the SF-52 condition
Other Syntactic Foam (Epoxy) grades and fills
Syntactic Foam (Epoxy) is listed in 13 conditions; see the grade overview at Syntactic Foam (Epoxy).
Compare all 13 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
0.32 g/cm³ shallow-water buoyancy grade | Maximum buoyancy for ROV/AUV and float applications rated to roughly 1000 m depth. | — | 6 | — | — |
Macrosphere/composite buoyancy module | Lowest-density option for large riser and drilling buoyancy modules, made by potting glass macrospheres in syntactic foam. | — | 6 | 1 | 74 Shore D |
Low-dielectric radome / antenna core grade | Very low density and loss tangent for radome cores, lenses and microwave absorber substrates. | — | 7 | 1.2 | 72 Shore D |
0.38 g/cm³ mid-depth buoyancy grade | Balanced buoyancy/strength choice for work-class ROVs and 3000 m rated equipment. | — | 9 | 1.2 | 76 Shore D |
Two-part pourable/castable syntactic compound | Field-mixed resin/microsphere paste for filling cavities, encapsulating cables and repairing buoyancy blocks. | — | 10 | 1.5 | 77 Shore D |
SF-45Default 0.45 g/cm³ deep-water buoyancy grade | The workhorse deep-water grade: adequate buoyancy with a safe hydrostatic margin to about 6000 m. | — | 12 | 1.5 | 80 Shore D |
Flame-retardant syntactic | For rail, marine interior and electronics enclosures needing V-0 and reduced smoke. | — | 13 | 1.2 | 82 Shore D |
SF-52This page 0.52 g/cm³ ultra-deep buoyancy grade | For hadal-zone floats and instrument housings where 7000–9000 m collapse margin is required. | — | 16 | 1.6 | 83 Shore D |
High-temperature epoxy syntactic | Choose for downhole tools, engine-bay or thermally cycled aerospace cores where 120–170 °C service is needed. | — | 17 | 1.2 | 86 Shore D |
Machinable epoxy syntactic tooling/model board | Dimensionally stable, low-CTE board for CNC master models, checking fixtures and vacuum-form tools. | — | 17 | 1 | 82 Shore D |
0.60 g/cm³ full-ocean-depth grade | Full-ocean-depth landers and manned submersibles, where crush strength outranks buoyancy efficiency. | — | 20 | 1.8 | 85 Shore D |
0.70 g/cm³ high-strength / structural core grade | Structural insert and load-bearing core grade where compressive strength, not buoyancy, governs. | — | 25 | 2 | 87 Shore D |
Chopped carbon/glass fibre reinforced syntactic | Adds fibre to raise flexural strength, toughness and crack resistance where the foam is load-bearing or impacted. | — | 35 | 1 | 85 Shore D |
What is Syntactic Foam (Epoxy) SF-52?
Syntactic Foam (Epoxy) SF-52 is Syntactic Foam (Epoxy) in the SF-52 grade — for hadal-zone floats and instrument housings where 7000–9000 m collapse margin is required. Syntactic Foam (Epoxy) SF-52 has a tensile strength of 16 MPa (2.32 ksi), weaker than 72% of polymer grades. Elongation at break is 1.6% and the elastic modulus is 3 GPa (0.435 Msi). Syntactic Foam (Epoxy) SF-52 has a density of 0.52 g/cm³ (0.0188 lb/in³), lighter than 84% of polymer grades. Its glass-transition temperature is 100°C (212 °F). SF-45 is the default condition FabDigit quotes; SF-52 is available on request or by drawing note.
Advantages
- Low, predictable mold shrinkage — 0.18%, better than 95% of polymer grades
- Lightweight — 0.52 g/cm³ (0.0188 lb/in³), better than 84% of polymer grades
- Low moisture uptake — 0.1%, better than 77% of polymer grades
Limitations
- Limited formability — 0/100, worse than 100% of polymer grades
- Difficult to weld — 0/100, worse than 98% of polymer grades
- Limited ductility — 1.6%, worse than 97% of polymer grades
- Hard to polish — 20/100, worse than 95% of polymer grades
- Low fracture toughness — 0.8 MPa·√m (0.728 ksi·√in), worse than 92% of polymer grades
Syntactic Foam (Epoxy) SF-52 properties
Typical room-temperature values for Syntactic Foam (Epoxy) SF-52; 24 are specific to this condition. Other listed values are Syntactic Foam (Epoxy) reference data and may not represent this condition. Bars are the position among polymer grades.
Physical4
Syntactic Foam (Epoxy) SF-52 has a density of 0.52 g/cm³ (0.0188 lb/in³), lighter than 84% of polymer grades. Its glass-transition temperature is 100°C (212 °F).
Mechanical15
Syntactic Foam (Epoxy) SF-52 has a tensile strength of 16 MPa (2.32 ksi), weaker than 72% of polymer grades. Elongation at break is 1.6% and the elastic modulus is 3 GPa (0.435 Msi).
Thermal10
Syntactic Foam (Epoxy) SF-52 is rated for continuous service to 80°C (176 °F). It conducts heat at 0.14 W/m·K (0.0809 BTU/hr·ft·°F), worse than 81% of polymer grades. Thermal expansion is 32 µm/m·K (17.8 µin/in·°F).
Electrical5
Syntactic Foam (Epoxy) SF-52 is an electrical insulator with a dielectric strength of 9 kV/mm (228.6 V/mil) and a resistivity of 1×10¹² Ω·m.
Chemical & Environmental3
Corrosion resistance is excellent (85/100), better than 65% of polymer grades. UV resistance is fair.
Sustainability3
Producing a kilogram of Syntactic Foam (Epoxy) SF-52 takes about 105 MJ of energy and emits 6 kg of CO₂ — more than 54% of polymer grades. Typical recycled content is 0%.
Manufacturability6
Syntactic Foam (Epoxy) SF-52's machinability is good (58/100, worse than 55% of polymer grades); weldability not recommended (0/100); formability not recommended (0/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Syntactic Foam (Epoxy) SF-52
Is Syntactic Foam (Epoxy) easy to machine?
Machines easily with sharp carbide or diamond tooling at high speed and low feed, dry with vacuum extraction; the glass microspheres are abrasive and the dust is a respiratory hazard, and cut faces are open-cell so they must be sealed or gelcoated.
Can Syntactic Foam (Epoxy) be welded?
Not weldable — a thermoset; joints are made with structural epoxy adhesive, and repairs use pourable syntactic putty of the same density class.
Can Syntactic Foam (Epoxy) be formed, bent or molded?
Produced by low-pressure casting, compression moulding or vacuum-assisted pouring of resin/microsphere paste into moulds, then oven cured and post-cured; avoid high pressure or aggressive mixing which crushes the microballoons and raises density.
What surface finishes work on Syntactic Foam (Epoxy)?
Sanded, then sealed with epoxy primer, polyurethane topcoat or elastomeric skin for UV, abrasion and long-term water-ingress protection; hardware is bonded in or potted rather than tapped into the foam.
Syntactic Foam (Epoxy) 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 |
|---|---|---|
| hollow glass microspheressoda-lime-borosilicate microballoons, 10–120 µm, 0.2–0.6 g/cm³ true density; 50–65 vol% | 25 – 50 | 40 |
| silane coupling agent / additivesadhesion promoter, thixotrope, pigment | 0 – 2 | 1 |
| hollow polymer microspheres (optional)used in low-strength shallow-water and RF grades | 0 – 5 | 0 |
| chopped glass or carbon fibre (CF/GF var | 0 – 15 | 0 |
| epoxy resin + amine/anhydride hardener (DGEBA or DGEBF based, cured system | ≥ 45 (balance) | — |
Syntactic Foam (Epoxy) SF-52 — frequently asked
What is Syntactic Foam (Epoxy) SF-52 used for?
Syntactic Foam (Epoxy) SF-52 is typically used for subsea buoyancy modules, deep-sea ROV/AUV floats, riser/cable buoyancy and aerospace tooling cores. In short: pressure-resistant buoyancy foam; machinable structural core; abrasive microsphere dust.
What is the tensile strength of Syntactic Foam (Epoxy) SF-52?
Syntactic Foam (Epoxy) SF-52 has a typical tensile strength of 16 MPa (2.32 ksi) — weaker than 72% of polymer grades. Strength varies by condition: see the 13 listed tempers.
Is Syntactic Foam (Epoxy) SF-52 easy to machine?
Reasonably — machinability is rated good (58/100, worse than 55% of polymer grades). Machines easily with sharp carbide or diamond tooling at high speed and low feed, dry with vacuum extraction; the glass microspheres are abrasive and the dust is a respiratory hazard, and cut faces are open-cell so they must be sealed or gelcoated.
Can Syntactic Foam (Epoxy) SF-52 be welded?
Not readily — weldability is rated not recommended (0/100). Not weldable — a thermoset; joints are made with structural epoxy adhesive, and repairs use pourable syntactic putty of the same density class.
What surface finishes work on Syntactic Foam (Epoxy) SF-52?
Sanded, then sealed with epoxy primer, polyurethane topcoat or elastomeric skin for UV, abrasion and long-term water-ingress protection; hardware is bonded in or potted rather than tapped into the foam.
Can Syntactic Foam (Epoxy) SF-52 be formed, bent or molded?
Produced by low-pressure casting, compression moulding or vacuum-assisted pouring of resin/microsphere paste into moulds, then oven cured and post-cured; avoid high pressure or aggressive mixing which crushes the microballoons and raises density.
What is the maximum service temperature of Syntactic Foam (Epoxy) SF-52?
Syntactic Foam (Epoxy) SF-52 is rated for continuous use to about 80°C (176 °F), and briefly to 105°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- Subsea buoyancy syntactic foam grade tables (density vs. depth rating) — Trelleborg Offshore (2023)
- Deep-submergence syntactic foam and macrosphere buoyancy products — Engineered Syntactic Systems (ESS) (2022)
- ASM Handbook Vol. 21: Composites — syntactic foams and core materials — ASM International (2001)
- Structure and properties of hollow-particle-filled polymer composites (review data) — Journal of Materials Science / Gupta et al. (2014)
- ASTM D2842 — Water Absorption of Rigid Cellular Plastics — ASTM (2019)
- ASTM D1621 — Compressive Properties of Rigid Cellular Plastics — ASTM (2016)
- Epoxy syntactic tooling/model board technical data — Ebalta / Sika Advanced Resins (2023)
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.