GB/T 10801.1 Type IV B2
Flame-retardant grade · default condition
B2 = gB 8624 B2 ≥30%
Default pick for building insulation and load-bearing levelling layers: the polymeric brominated flame retardant gives an oxygen index of at least 30% and satisfies GB 8624 B2.
Values for the B2 condition
Other GB/T 10801.1 Type IV grades and fills
GB/T 10801.1 Type IV is listed in 4 conditions; see the grade overview at GB/T 10801.1 Type IV.
Compare all 4 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
graphite-enhanced (grey) EPS | Pick the graphite-modified grey board at 40 kg/m³ for thin high-efficiency insulation: flake graphite reflects infrared and cuts conductivity 10–15% to 0.030 W/m·K at equal density. | — | 0.38 | 1.7 | — |
GB 8624 B1 | Use where fire classification B1 is mandated, such as external wall insulation on high-rise buildings; the higher retardant dosage raises the oxygen index but adds cost. | — | 0.4 | 1.8 | — |
B2DefaultThis page GB 8624 B2 ≥30% | Default pick for building insulation and load-bearing levelling layers: the polymeric brominated flame retardant gives an oxygen index of at least 30% and satisfies GB 8624 B2. | — | 0.42 | 2 | — |
standard (non-flame-retardant) grade | Choose the non-flame-retardant version for packaging cushions, patterns and lightweight fill where no fire rating applies; it is the cheapest option but not for building envelopes. | — | 0.45 | 2.2 | — |
What is GB/T 10801.1 Type IV B2?
GB/T 10801.1 Type IV B2 is GB/T 10801.1 Type IV in the B2 grade — default pick for building insulation and load-bearing levelling layers: the polymeric brominated flame retardant gives an oxygen index of at least 30% and satisfies GB 8624 B2. GB/T 10801.1 Type IV B2 has a tensile strength of 0.42 MPa (0.0609 ksi), weaker than 91% of polymer grades. Elongation at break is 2% and the elastic modulus is 0.01 GPa (0.0017 Msi). GB/T 10801.1 Type IV B2 has a density of 0.04 g/cm³ (0.0014 lb/in³), lighter than 91% of polymer grades. Its glass-transition temperature is 100°C (212 °F).
Advantages
- Easy to machine — 92/100, better than 99% of polymer grades
- Lightweight — 0.04 g/cm³ (0.0014 lb/in³), better than 91% of polymer grades
Limitations
- Limited ductility — 2%, worse than 95% of polymer grades
- Poor heat conductor — 0.03 W/m·K (0.0191 BTU/hr·ft·°F), worse than 95% of polymer grades
- Degrades in UV without stabilisers — 18/100, worse than 93% of polymer grades
- Absorbs moisture — dry before molding — 1%, worse than 84% of polymer grades
- Low stiffness — 0.01 GPa (0.0017 Msi), worse than 79% of polymer grades
GB/T 10801.1 Type IV B2 properties
Typical room-temperature values for GB/T 10801.1 Type IV B2; 18 are specific to this condition. Other listed values are GB/T 10801.1 Type IV reference data and may not represent this condition. Bars are the position among polymer grades.
Physical4
GB/T 10801.1 Type IV B2 has a density of 0.04 g/cm³ (0.0014 lb/in³), lighter than 91% of polymer grades. Its glass-transition temperature is 100°C (212 °F).
Mechanical11
GB/T 10801.1 Type IV B2 has a tensile strength of 0.42 MPa (0.0609 ksi), weaker than 91% of polymer grades. Elongation at break is 2% and the elastic modulus is 0.01 GPa (0.0017 Msi).
Thermal8
GB/T 10801.1 Type IV B2 is rated for continuous service to 75°C (167 °F). It conducts heat at 0.03 W/m·K (0.0191 BTU/hr·ft·°F), worse than 95% of polymer grades. Thermal expansion is 65 µm/m·K (36.1 µin/in·°F).
Electrical4
GB/T 10801.1 Type IV B2 has an electrical resistivity of 1×10¹⁴ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (80/100), worse than 52% of polymer grades. UV resistance is poor.
Sustainability4
Producing a kilogram of GB/T 10801.1 Type IV B2 takes about 105 MJ of energy and emits 3.5 kg of CO₂ — more than 54% of polymer grades. Typical recycled content is 5%.
Manufacturability4
GB/T 10801.1 Type IV B2's machinability is excellent (92/100, better than 99% of polymer grades); weldability poor (25/100); formability poor (20/100).
Common Calculations4
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with GB/T 10801.1 Type IV B2
Is GB/T 10801.1 Type IV easy to machine?
Hot-wire cutting, band sawing and high-speed milling all work; feed rates can be fast and tool wear is negligible. Use dust extraction to control static-charged debris.
Can GB/T 10801.1 Type IV be welded?
Blocks can be joined by steam re-moulding or hot-wire/hot-air fusion, but joint strength is below that of the parent foam; low-solvent water-based adhesive or mechanical anchoring is usually preferred.
Can GB/T 10801.1 Type IV be formed, bent or molded?
Pre-expanded beads are aged, then steam moulded at 0.08–0.12 MPa steam. Moulded blocks need 1–3 days of aging to stabilise dimensions before cutting.
What surface finishes work on GB/T 10801.1 Type IV?
Surfaces must be protected with cement-based crack-resistant mortar, mesh cloth or a facing panel. Avoid solvent-based coatings and bitumen adhesives, and never leave the foam bare in UV or near open flame.
GB/T 10801.1 Type IV 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 |
|---|---|---|
| pentanemostly escapes after curing and is replaced by air | 0.2 – 1.5 | 0.7 |
| brominated polymeric flame retardant (flame-retardant types only; HBCD replaced by polymeric FR | 0.3 – 1.5 | 0.8 |
| graphiteonly graphite-modified grey board variants contain 2–4% | 0 – 4 | 0 |
| talc / nucleating & antistatic additives | 0 – 0.5 | 0.2 |
| polystyrenemoulded from expandable polystyrene (EPS) beads | ≥ 96 (balance) | — |
GB/T 10801.1 Type IV B2 — frequently asked
What is GB/T 10801.1 Type IV B2 used for?
GB/T 10801.1 Type IV B2 is typically used for heavy-load geofoam fill, industrial floor insulation, under-slab insulation for cold stores, load-bearing structural insulated panel cores, road and embankment lightweight fill and foundation perimeter insulation. In short: highest-strength EPS class; heavy-load geofoam grade.
What is the tensile strength of GB/T 10801.1 Type IV B2?
GB/T 10801.1 Type IV B2 has a typical tensile strength of 0.42 MPa (0.0609 ksi) — weaker than 91% of polymer grades. Strength varies by condition: see the 4 listed tempers.
Is GB/T 10801.1 Type IV B2 easy to machine?
Yes — machinability is rated excellent (92/100, better than 99% of polymer grades). Hot-wire cutting, band sawing and high-speed milling all work; feed rates can be fast and tool wear is negligible. Use dust extraction to control static-charged debris.
Can GB/T 10801.1 Type IV B2 be welded?
Not readily — weldability is rated poor (25/100). Blocks can be joined by steam re-moulding or hot-wire/hot-air fusion, but joint strength is below that of the parent foam; low-solvent water-based adhesive or mechanical anchoring is usually preferred.
What surface finishes work on GB/T 10801.1 Type IV B2?
Surfaces must be protected with cement-based crack-resistant mortar, mesh cloth or a facing panel. Avoid solvent-based coatings and bitumen adhesives, and never leave the foam bare in UV or near open flame.
Can GB/T 10801.1 Type IV B2 be formed, bent or molded?
Pre-expanded beads are aged, then steam moulded at 0.08–0.12 MPa steam. Moulded blocks need 1–3 days of aging to stabilise dimensions before cutting.
What is the maximum service temperature of GB/T 10801.1 Type IV B2?
GB/T 10801.1 Type IV B2 is rated for continuous use to about 75°C (167 °F), and briefly to 95°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- ASTM C578 Standard Specification for Rigid, Cellular Polystyrene Thermal Insulation — ASTM (2022)
- ASM Handbook Vol. 2 / Engineered Materials — Cellular Plastics — ASM International (1988)
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.