Basalt Fiber HT
Heat-treated state
GB GB/T 25045
HT = high-temperature / high-modulus grade
Select the ore-selected melt with controlled Fe/Ti and low alkali when 95 GPa modulus and 680 °C service are required for friction, thermal-insulation and aerospace parts.
Values for the HT condition
Other Basalt Fiber grades and fills
Basalt Fiber is listed in 6 conditions; see the grade overview at Basalt Fiber.
Compare all 6 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Basalt mineral wool | Choose this discontinuous ultra-fine fibre board or blanket when 0.038 W/m·K conductivity, non-combustibility and 650 °C service matter rather than mechanical strength. | — | 0.01 | — | — |
Chopped strand mat / needled mat | Pick the chopped strand or needled mat for hand lay-up laminates and fire-protection insulating layers; it wets out fast but is randomly oriented, so properties are isotropic and low. | — | 130 | 1.8 | — |
BFRP rebar / pultruded rod (epoxy or vinyl-ester matrix) | Use the pultruded rebar or rod to replace steel bar in marine, tunnel-boring and de-icing-salt environments: non-corroding and non-magnetic, but modulus is a quarter of steel and it cannot be bent on site. | — | 1,100 | 2.3 | — |
Milled fibre | Pick 0.1–1 mm milled micro-fibre as a reinforcing filler in friction materials, coatings, adhesives and resins, replacing asbestos and milled glass fibre, at 2500 MPa fibre strength. | — | 2,500 | 3 | — |
Chopped strand | Use 3–24 mm chopped strand to control cracking and toughen cement-based materials or to reinforce PP/PA moulding compounds; alkali resistance allows direct use in concrete. | — | 2,900 | 3.1 | — |
HTThis page High-temperature / high-modulus grade | Select the ore-selected melt with controlled Fe/Ti and low alkali when 95 GPa modulus and 680 °C service are required for friction, thermal-insulation and aerospace parts. | — | 3,300 | 3.2 | — |
What is Basalt Fiber HT?
Basalt Fiber HT is Basalt Fiber heat treated to HT — select the ore-selected melt with controlled Fe/Ti and low alkali when 95 GPa modulus and 680 °C service are required for friction, thermal-insulation and aerospace parts. Basalt Fiber HT has a tensile strength of 3,300 MPa (479 ksi), stronger than 84% of composite grades. Elongation at break is 3.2% and the elastic modulus is 95 GPa (13.8 Msi). Basalt Fiber HT has a density of 2.67 g/cm³ (0.0965 lb/in³), heavier than 84% of composite grades.
Advantages
- Low embodied carbon — 1.8 kg CO₂/kg, better than 98% of composite grades
- Low moisture uptake — 0.05%, better than 94% of composite grades
- High service temperature — 680°C (1,256 °F), better than 89% of composite grades
- Good corrosion resistance — 90/100, better than 85% of composite grades
- Ductile — tolerates forming and impact — 3.2%, better than 78% of composite grades
Limitations
- Poor heat conductor — 0.04 W/m·K (0.0231 BTU/hr·ft·°F), worse than 91% of composite grades
- Heavy — 2.67 g/cm³ (0.0965 lb/in³), worse than 84% of composite grades
- Difficult to machine — 18/100, worse than 80% of composite grades
Basalt Fiber HT properties
Typical room-temperature values for Basalt Fiber HT; 11 are specific to this condition. Other listed values are Basalt Fiber reference data and may not represent this condition. Bars are the position among composite grades.
Physical3
Basalt Fiber HT has a density of 2.67 g/cm³ (0.0965 lb/in³), heavier than 84% of composite grades.
Mechanical6
Basalt Fiber HT has a tensile strength of 3,300 MPa (479 ksi), stronger than 84% of composite grades. Elongation at break is 3.2% and the elastic modulus is 95 GPa (13.8 Msi).
Thermal8
Basalt Fiber HT is rated for continuous service to 680°C (1,256 °F). It conducts heat at 0.04 W/m·K (0.0231 BTU/hr·ft·°F), worse than 91% of composite grades. Thermal expansion is 8 µm/m·K (4.44 µin/in·°F).
Electrical2
Basalt Fiber HT has an electrical resistivity of 1×10¹³ Ω·m.
Chemical & Environmental3
Corrosion resistance is excellent (90/100), better than 85% of composite grades. UV resistance is excellent.
Sustainability4
Producing a kilogram of Basalt Fiber HT takes about 22 MJ of energy and emits 1.8 kg of CO₂ — less than 98% of composite grades. Typical recycled content is 0%.
Manufacturability1
Basalt Fiber HT's machinability is poor (18/100, worse than 80% of composite grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Basalt Fiber HT
Is Basalt Fiber easy to machine?
Cured basalt-fiber composites are highly abrasive; use diamond or PCD tooling at high spindle speed and low feed with dust extraction to avoid delamination and edge burrs.
Can Basalt Fiber be welded?
Inorganic fiber cannot be welded; BFRP parts are joined by adhesive bonding, mechanical fastening or co-curing with the resin.
Can Basalt Fiber be formed, bent or molded?
Suitable for pultrusion, filament winding, vacuum infusion, RTM, SMC/BMC and chopped-fiber reinforced injection moulding. The fiber is brittle, so control bend radius and tension during processing; finished parts cannot be bent a second time.
What surface finishes work on Basalt Fiber?
The sizing determines resin adhesion and must be matched to the matrix system. Seal cut edges with resin and use mineral-fiber dust protection when cutting or handling.
Basalt Fiber 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 |
|---|---|---|
| SiO2network former; varies with ore source | 45 – 60 | 52 |
| Al2O3 | 12 – 19 | 16 |
| Fe2O3+FeOiron oxides give the fiber its gold-brown color | 5 – 15 | 10 |
| CaO | 5 – 12 | 8.5 |
| MgO | 3 – 8 | 5 |
| Na2O+K2Oalkali content affects hydrolysis resistance | 1.5 – 6 | 3.5 |
| TiO2 | 0.5 – 2.5 | 1.2 |
| sizing (silane, )surface coating, not counted in the glass phase | 0.3 – 1.5 | 0.7 |
| (MnO, P2O5, SO3) | ≥ 0 (balance) | — |
Basalt Fiber HT — frequently asked
What is Basalt Fiber HT used for?
Basalt Fiber HT is typically used for rebar reinforcement, fireproof textiles, automotive and marine composites and geotextiles. In short: stiffer than E-glass; service to 600 C; good alkali resistance.
What is the tensile strength of Basalt Fiber HT?
Basalt Fiber HT has a typical tensile strength of 3,300 MPa (479 ksi) — stronger than 84% of composite grades. Strength varies by condition: see the 6 listed tempers.
Is Basalt Fiber HT easy to machine?
Not especially — machinability is rated poor (18/100, worse than 80% of composite grades). Cured basalt-fiber composites are highly abrasive; use diamond or PCD tooling at high spindle speed and low feed with dust extraction to avoid delamination and edge burrs.
Can Basalt Fiber HT be welded?
Inorganic fiber cannot be welded; BFRP parts are joined by adhesive bonding, mechanical fastening or co-curing with the resin.
What surface finishes work on Basalt Fiber HT?
The sizing determines resin adhesion and must be matched to the matrix system. Seal cut edges with resin and use mineral-fiber dust protection when cutting or handling.
Can Basalt Fiber HT be formed, bent or molded?
Suitable for pultrusion, filament winding, vacuum infusion, RTM, SMC/BMC and chopped-fiber reinforced injection moulding. The fiber is brittle, so control bend radius and tension during processing; finished parts cannot be bent a second time.
What is the maximum service temperature of Basalt Fiber HT?
Basalt Fiber HT is rated for continuous use to about 680°C (1,256 °F), and briefly to 960°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- Continuous Basalt Fiber Roving technical data — Kamenny Vek / (2023)
- ASM Handbook Vol. 21: Composites — inorganic fibres — ASM International (2001)
- Basalt fibre property compilations (Composites Part B / Construction & Building Materials reviews) — Elsevier (2020)
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.