PC-Foam SF-LD
Grade
SF-LD = low-density structural foam, 25–40 % weight reduction
Maximum weight and resin saving for very thick, lightly loaded panels and cores; accept the large drop in strength and impact.
Values for the SF-LD condition
Other PC-Foam grades and fills
PC-Foam is listed in 5 conditions; see the grade overview at PC-Foam.
Compare all 5 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
SF-LDThis page Low-density structural foam, 25–40 % weight reduction | Maximum weight and resin saving for very thick, lightly loaded panels and cores; accept the large drop in strength and impact. | — | 30 | 6 | — |
Flame-retardant foamed PC, UL 94 V-0 | Required for electrical enclosures, IT/telecom housings and rail interiors where a V-0 rating at the actual wall thickness must be certified. | 40 | 42 | 12 | 62 HRM |
SF-CBADefault Chemical-blown structural foam, 10–20 % weight reduction | Standard low-pressure structural foam molding with a CBA masterbatch — pick for thick-wall covers, enclosures and pallets where sink-mark-free rigidity matters more than surface finish. | 43 | 45 | 18 | 62 HRM |
MuCell / microcellular | Choose when tight dimensional control, thin walls and near-solid surface quality are needed alongside modest weight and cycle-time savings. | 53 | 55 | 25 | 68 HRM |
20 % glass-fiber reinforced structural foam | Use when a foamed part still needs high stiffness, low creep and low CTE — e.g. load-bearing housings and machine bases. | — | 70 | 2.5 | — |
What is PC-Foam SF-LD?
PC-Foam SF-LD is PC-Foam in the SF-LD grade — maximum weight and resin saving for very thick, lightly loaded panels and cores; accept the large drop in strength and impact. PC-Foam SF-LD has a yield strength of 43 MPa (6.24 ksi) and a tensile strength of 30 MPa (4.35 ksi) — weaker than 61% of polymer grades. Elongation at break is 6% and the elastic modulus is 1.2 GPa (0.174 Msi). PC-Foam SF-LD has a density of 0.8 g/cm³ (0.0289 lb/in³), lighter than 83% of polymer grades. Its glass-transition temperature is 147°C (297 °F). SF-CBA is the default condition FabDigit quotes; SF-LD is available on request or by drawing note.
Advantages
- Lightweight — 0.8 g/cm³ (0.0289 lb/in³), better than 83% of polymer grades
Limitations
- Hard to polish — 20/100, worse than 95% of polymer grades
- Poor heat conductor — 0.12 W/m·K (0.0693 BTU/hr·ft·°F), worse than 83% of polymer grades
PC-Foam SF-LD properties
Typical room-temperature values for PC-Foam SF-LD; 11 are specific to this condition. Other listed values are PC-Foam reference data and may not represent this condition. Bars are the position among polymer grades.
Physical4
PC-Foam SF-LD has a density of 0.8 g/cm³ (0.0289 lb/in³), lighter than 83% of polymer grades. Its glass-transition temperature is 147°C (297 °F).
Mechanical16
PC-Foam SF-LD has a yield strength of 43 MPa (6.24 ksi) and a tensile strength of 30 MPa (4.35 ksi) — weaker than 61% of polymer grades. Elongation at break is 6% and the elastic modulus is 1.2 GPa (0.174 Msi).
Thermal11
PC-Foam SF-LD is rated for continuous service to 110°C (230 °F). It conducts heat at 0.12 W/m·K (0.0693 BTU/hr·ft·°F), worse than 83% of polymer grades. Thermal expansion is 68 µm/m·K (37.8 µin/in·°F).
Electrical7
PC-Foam SF-LD is an electrical insulator with a dielectric strength of 18 kV/mm (457.2 V/mil) and a resistivity of 1×10¹⁴ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (82/100), better than 56% of polymer grades. UV resistance is fair.
Sustainability4
Producing a kilogram of PC-Foam SF-LD takes about 105 MJ of energy and emits 6 kg of CO₂ — more than 54% of polymer grades. Typical recycled content is 10%.
Manufacturability8
PC-Foam SF-LD's machinability is good (62/100, better than 60% of polymer grades); weldability fair (50/100); formability poor (30/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with PC-Foam SF-LD
Is PC-Foam easy to machine?
Cuts easily with sharp single-flute or O-flute tools and high rake; use light climb passes and avoid heat build-up, and expect exposed open cells at cut edges that must be sealed or edge-banded.
Can PC-Foam be welded?
Hot-plate, ultrasonic (near-field, low amplitude) and vibration welding all work only through the dense skin — joint strength is roughly 40–60 % of solid PC; solvent bonding with methylene-chloride blends or 2K PUR/epoxy adhesives is more reliable.
Can PC-Foam be formed, bent or molded?
Low-pressure structural foam or gas-counterpressure molding on a nitrogen or CBA-equipped machine; dry resin ≤0.02 % moisture (120 °C, 4 h), melt 265–305 °C, mold 55–95 °C, wall 4–10 mm, fast fill with short shot plus 10–20 % expansion.
What surface finishes work on PC-Foam?
As-molded swirl and silver streaks are normal: standard route is sand/fill, adhesion-promoter primer, then 2K PU or waterborne topcoat; gas-counterpressure or in-mold film gives a paintable class-B surface, and PC foam accepts vacuum metallizing only after sealing.
PC-Foam 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 |
|---|---|---|
| chemical blowing agent masterbatchendothermic sodium bicarbonate/citric acid or exothermic azodicarbonamide type; replaced by N₂/CO₂ gas in physical (MuCell) foaming | 0.3 – 3 | 1 |
| nucleating agent / talccell-size control | 0 – 1 | 0.3 |
| heat and hydrolysis stabilizer (phosphit | 0.05 – 0.5 | 0.2 |
| glass fiberonly in reinforced foam variants (GF10–GF30) | 0 – 30 | 0 |
| flame retardant (sulfonate salt / phosphFR V-0 variants only | 0 – 12 | 0 |
| bisphenol-A polycarbonatemelt-polycondensation or interfacial BPA-PC resin, typically 8–20 g/10 min MFR foam grade | ≥ 96 (balance) | — |
PC-Foam SF-LD — frequently asked
What is PC-Foam SF-LD used for?
PC-Foam SF-LD is typically used for large enclosures, furniture components, equipment panels and weight-reduced structural parts. In short: lightest structural PC; thick-wall low-pressure molding; rigid weight-saving enclosure resin.
What is the yield strength of PC-Foam SF-LD?
PC-Foam SF-LD has a typical yield strength of 43 MPa (6.24 ksi) and a tensile strength of 30 MPa (4.35 ksi) — weaker than 61% of polymer grades. Strength varies by condition: see the 5 listed tempers.
Is PC-Foam SF-LD easy to machine?
Reasonably — machinability is rated good (62/100, better than 60% of polymer grades). Cuts easily with sharp single-flute or O-flute tools and high rake; use light climb passes and avoid heat build-up, and expect exposed open cells at cut edges that must be sealed or edge-banded.
Can PC-Foam SF-LD be welded?
With care — weldability is rated fair (50/100). Hot-plate, ultrasonic (near-field, low amplitude) and vibration welding all work only through the dense skin — joint strength is roughly 40–60 % of solid PC; solvent bonding with methylene-chloride blends or 2K PUR/epoxy adhesives is more reliable.
What surface finishes work on PC-Foam SF-LD?
As-molded swirl and silver streaks are normal: standard route is sand/fill, adhesion-promoter primer, then 2K PU or waterborne topcoat; gas-counterpressure or in-mold film gives a paintable class-B surface, and PC foam accepts vacuum metallizing only after sealing.
Can PC-Foam SF-LD be formed, bent or molded?
Low-pressure structural foam or gas-counterpressure molding on a nitrogen or CBA-equipped machine; dry resin ≤0.02 % moisture (120 °C, 4 h), melt 265–305 °C, mold 55–95 °C, wall 4–10 mm, fast fill with short shot plus 10–20 % expansion.
What is the maximum service temperature of PC-Foam SF-LD?
PC-Foam SF-LD is rated for continuous use to about 110°C (230 °F), and briefly to 135°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between PC-Foam SF-CBA and PC-Foam MUCELL?
SF-CBA is the default condition — standard low-pressure structural foam molding with a CBA masterbatch — pick for thick-wall covers, enclosures and pallets where sink-mark-free rigidity matters more than surface finish. MUCELL: choose when tight dimensional control, thin walls and near-solid surface quality are needed alongside modest weight and cycle-time savings. Yield strength is 43 MPa in SF-CBA versus 53 MPa in MUCELL.
Sources
- Engineered Materials Handbook Vol. 2: Engineering Plastics — ASM International (1988)
- Handbook of Polymeric Foams and Foam Technology — Hanser (2004)
- ISO 7391 Plastics — Polycarbonate (PC) moulding and extrusion materials — ISO (2006)
- ASTM D3935 Standard Classification System for Polycarbonate Molding and Extrusion Materials — ASTM (2017)
- CAMPUS plastics database — polycarbonate injection grades — CWFG / CAMPUS consortium (2024)
- Structural foam and microcellular (MuCell) processing guides for polycarbonate — Covestro / SABIC / Trexel (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.