Boron Nitride Fiber Paper & Felt for High-Temperature Non-Wetting Insulation

Boron Nitride Fiber Applications

• Industrial Thermal Processing (Vacuum/Sintering/Brazing)

  ✅Key Advantages

  1. Dimensional stability in vacuum: Precise and predictable thickness helps maintain tight seal gaps at furnace doors, windows, and baffles, ensuring uniform heat distribution and minimizing gas leakage.
  2. Low outgassing and clean processing: BN fiber paper/felt emits minimal volatiles, supporting stable base pressures (<10⁻⁵ mbar) and preventing contamination of heating elements, thermocouples, and optical ports.
  3. Electrical insulation at high temperature: Provides a consistent dielectric barrier (~10–20 kV/mm) between heaters, graphite fixtures, and metallic supports, ensuring electrical safety and preventing arcing during high-current operations.

  ✅ Problem Solved

  A brazing furnace manufacturer replaced conventional aluminosilicate fiber paper with 0.5 mm BN fiber gaskets for its vacuum door seals. As a result, fixture readjustment time decreased by 30%, base pressure recovery improved from 3.0×10⁻⁴ to 1.5×10⁻⁵ mbar, and leak-test failures dropped significantly over two service cycles due to stable thickness, reduced particle shedding, and improved sealing uniformity.

• Non-Wetting Separation for Aluminum/Magnesium Casting

  ✅Key Advantages

  1. Non-wetting and corrosion resistance: BN fiber’s low surface energy prevents adhesion of molten Al/Mg, extending component life and simplifying post-run cleaning.
  2. Custom-fit liners and gaskets: Cut-to-shape sheets fit casting troughs, weirs, and baffles precisely, maintaining flow consistency while avoiding metal accumulation and blockages.
  3. Thermal shock resistance: Maintains structure during rapid heating or cooling cycles (up to 900–1000 °C in air, >1800 °C in inert gas), supporting continuous casting and die-change operations.

  ✅ Problem Solved

  An aluminum foundry integrated 1–3 mm BN fiber liners in its launder and filter chamber. After installation, metal adhesion decreased visibly, cleaning intervals were extended from every 2 days to every 5–6 days, and downtime dropped by over 40%, improving total throughput and labor efficiency without altering the alloy chemistry.

• Electronics & Power Device Tooling

  ✅Key Advantages

  1. High dielectric reliability: Stable insulation under elevated temperature and voltage prevents shorting between powered fixtures and conductive components.
  2. Low particle generation: Compacted BN fiber surfaces minimize dust, supporting cleanroom integration for semiconductor and display manufacturing.
  3. Thermal buffering and uniformity: Tunable density allows controlled heat flow between heating elements and sensitive substrates, reducing hot spots and improving repeatability.

  ✅ Problem Solved

  A tooling integrator replaced mica sheets with 0.8 mm pressed BN fiber insulation pads in high-power bonding jigs. The change improved electrical isolation margins by >25%, stabilized temperature uniformity within ±2 °C, and extended pad replacement cycles from 2 weeks to 6 weeks due to superior structural retention and surface integrity.

Boron Nitride Fiber Usage Instructions

• Installation

  1. Verify thickness and density at 3–5 measurement points before assembly to ensure gauge uniformity.
  2. Orient any pressed or compacted face consistently toward the specified direction (e.g., release side toward molten metal).
  3. For die-cut gasket sets, follow station labels or numbered positions to maintain sealing order and prevent mismatch.
  4. Perform a dry-fit check before final heating or fastening; adjust alignment to avoid local stress or overlap.
  5. Avoid excessive compression at bolts or clamps—BN fiber performs best with light to moderate seating pressure (typically ≤ 0.3 MPa).

• Operation

  1. Match the BN grade to the operating atmosphere:
  a. Air use ≤ 900–1000 °C
  b. Vacuum/inert gases ≤ 1800 °C
  2. Allow gradual heating and cooling to minimize thermal shock.
  3. When used with molten aluminum or magnesium, ensure contact occurs only on the release side to maintain non-wetting performance.
  4. For electrical insulation applications, verify clearance vs. voltage rating (10–20 kV/mm typical) and confirm grounding integrity.
  5. Avoid direct contact with reactive vapors (halogens, steam, or alkali oxides) that may degrade fiber bonding.

• Storage

  1. Keep all sheets and die-cut parts flat, sealed, and clearly labeled by thickness and grade.
  2. Store in a dry, temperature-controlled area (≤40% RH), away from abrasive materials or direct sunlight.
  3. For long-term storage, place interleaf sheets or plastic liners between layers to prevent fiber abrasion or compression deformation.

• Cleaning & Handling

  1. Use low-lint wipes or vacuum cleaning to remove surface dust; never blow with compressed air.
  2. Handle using clean gloves to prevent oil contamination.
  3. Do not rub or flex edges; the material should be lifted, not dragged, during transfer.
  4. If a sheet becomes frayed, delaminated, or contaminated, replace it rather than attempting repair to maintain process cleanliness.

• Common Mistakes & Fixes

  1. Over-clamping causes edge denting
  → Use torque control, flat washers, or soft spacers to distribute pressure evenly.

  2. Random orientation of faces
  → Mark the release face before cutting and ensure all parts are installed with consistent orientation to avoid wetting or uneven sealing.

  3. Using thin gauge for large unsupported spans
  → Increase thickness or integrate graphite/oxide fiber backing plates for stability.

  4. Improper heating rate
  → Ramp temperature gradually (≤5 °C/min) to prevent microcrack formation or fiber lift-off.

  5. Contamination from handling tools
  → Dedicate clean stainless or ceramic tools for cutting and installation to avoid residue transfer.

Boron Nitride Nanotubes Fiber FAQ

1. Q: What is boron nitride fiber paper used for?
   A: Boron nitride fiber paper is mainly used for non-wetting separation and electrical insulation in vacuum furnaces, metal casting, and electronics tooling, providing a clean, low-outgassing barrier at high temperature.
2. Q: How does boron nitride fiber differ from alumina or mica insulation paper?
   A: Unlike alumina or mica, BN fiber is non-wetting to aluminum and magnesium, offers higher dielectric strength (~10–20 kV/mm), and generates less dust under thermal cycling—making it ideal for clean or reactive environments.
3. Q: Can boron nitride fiber be used in direct contact with molten aluminum or magnesium?
   A: Yes. BN fiber’s low surface energy and chemical inertness prevent metal adhesion and corrosion. It’s widely used as liners, spacers, and gaskets in Al/Mg casting lines.
4. Q: Can boron nitride fiber sheets be custom-cut or laminated?
   A: Absolutely. ADCERAX offers custom die-cut BN fiber gaskets (±0.1 mm tolerance), BN-to-graphite laminates, and pressed-face or backed versions for enhanced strength and surface cleanliness.
5. Q: Does boron nitride fiber generate particles or dust?
   A: Pressed or compacted grades have very low particle release. For ultra-clean environments, specify pressed surface finish or vacuum-packaged sheets to minimize fiber shedding.
6. Q: What information is required to quote custom BN fiber parts?
   A: Provide thickness, density grade, working atmosphere, and CAD drawing (DXF/DWG/PDF) with any surface finish or lamination requests. Typical drawing reviews are completed within 48 hours for quotation.

Boron Nitride Fiber Reviews

• ⭐️⭐️⭐️⭐️⭐️
  We integrated boron nitride fiber paper into our vacuum brazing fixtures. The uniform thickness and low outgassing significantly improved sealing stability during high-vacuum runs.
  --  David H., Senior Process Engineer, ThermoVac Systems Inc.
• ⭐️⭐️⭐️⭐️⭐️
  Our maintenance team switched to BN fiber felt liners for magnesium casting channels. The non-wetting surface cut cleaning time by half and eliminated residue sticking on the trough walls.
  -- Laura P., Production Manager, AlloyPro Foundry
• ⭐️⭐️⭐️⭐️⭐️
  We ordered custom-cut boron nitride fiber gaskets for our furnace doors. ADCERAX delivered precise dimensions and consistent quality, perfectly matching our drawing tolerances.
  -- Michael R., Procurement Lead, HeatTreat Engineering Ltd.
• ⭐️⭐️⭐️⭐️⭐️
  Our R&D lab tested several insulation materials, and the boron nitride fiber paper from ADCERAX showed the best dimensional stability and clean performance during repeated 1000 °C furnace cycles.
  -- Elena M., Materials Scientist, NovaTech Laboratories