Alumina Sheet (Al₂O₃ Ceramic Sheets) for Industrial Insulation, Wear Liners & Lab Fixtures

Alumina Al2O3 Sheet Applications

• Industrial Electrical Insulation

  ✅Key Advantages

  1. Controlled thickness ±0.05 mm keeps clamp pressure uniform and reduces insulation gap variation.

  2. Dielectric strength >10 kV/mm ensures stable insulation even after 500+ thermal cycles.

  3. Polished surfaces (Ra <0.05 μm) enhance adhesive wetting and reduce edge chipping in assembly.

  ✅ Problem Solved

  In a retrofit of inverter drives, polymer insulation pads degraded after repeated cycling, causing leakage and re-torque events. By switching to a thickness-controlled alumina ceramic sheet, insulation gaps remained consistent over 500+ heating cycles. This lowered rework calls by more than 20% and shortened maintenance windows, enabling stable module performance during production shifts.

• Manufacturing & Automation Engineering

  ✅Key Advantages

  1. Hardness >15 GPa prevents groove formation under repeated fixture contact loads.
  2. Chamfered edges (0.5–2 mm) minimize stress risers and improve operator safety in handling.
  3. Porosity <1% reduces coolant and abrasive infiltration, extending fixture life cycles.

  ✅ Problem Solved

  Automation fixtures previously grooved within 4–6 weeks, requiring frequent regrinding and downtime. After adopting Al2O3 ceramic sheet liners with specified edge chamfers and low-porosity grade, fixture life extended to cover full quarterly maintenance cycles. This reduced unplanned stops, improved operator safety, and cut spare kit consumption by nearly 30%.

• Laboratory & Heat Treatment Industry

  ✅Key Advantages

  1. Flatness control ≤0.1 mm across 100 mm span prevents sample tilt during high-temperature cycles.
  2. Thermal stability up to 1600 °C ensures repeated furnace runs without warping or sagging.
  3. Chemical inertness resists contamination in oxidative and neutral furnace atmospheres.

  ✅ Problem Solved

  Research labs using metallic carriers reported sample tilt and contamination after repeated furnace cycles. Replacing them with flatness-tiered alumina ceramic sheets kept carriers planar and inert across dozens of 1500 °C runs. This improved reproducibility of material tests, eliminated cross-contamination, and reduced sample wastage by more than 15% per quarter.

Alumina Sheet Usage Instructions

• Use

  1. Check tolerance vs. design needs: Confirm thickness class (±0.05 / ±0.10 / ±0.20 mm) and flatness tier align with your clamp, creepage, or bonding requirements.
  2. Prepare mating surfaces: Deburr and clean metal parts to prevent point loads; avoid sharp fasteners or uneven clamping pressure on edges.
  3. Bonding or adhesive prep: Degrease with isopropanol or compatible solvent; dry thoroughly before applying paste or film adhesive. Validate bake-out schedule to avoid thermal mismatch.
  4. Torque guidance: Use torque-controlled fastening; excessive force may cause edge cracks. Recommended clamp pressure <20 MPa for thin sheets.
  5. Thermal cycling: Ramp heating and cooling gradually (<5 °C/min for sheets <1 mm thick) to minimize thermal shock risk.

• Storage

  1. Flat positioning: Store on cushioned trays or racks with clean, non-abrasive surfaces.
  2. Separation: Stack by thickness/grade using interleaves of soft paper or foam; this prevents surface scratching and edge-to-edge contact.
  3. Environment: Keep in a dry, dust-free cabinet; avoid exposure to moisture that may lead to surface contamination.
  4. Labelling: Maintain batch ID and thickness/grade labels to ensure correct retrieval for reorders and process traceability.

• Cleaning

  1. Routine cleaning: Rinse in deionized water or mild neutral detergent solution; air or oven dry at ≤100 °C to prevent spotting.
  2. Residue removal: For adhesive/paste residues, use non-contaminating abrasive pads or fine alumina slurry polishing; re-inspect flatness afterward.
  3. Avoid: Do not use strong alkaline cleaners or steel wool, as they may contaminate or scratch the ceramic surface.
  4. Final prep: Before bonding or metallization, perform ultrasonic cleaning (if required) followed by controlled drying in clean airflow.

• Common Misuse & Fix

  1. Over-tightening clamps → Use torque-controlled fasteners and request chamfered edges to distribute stress.
  2. Edge impacts → Handle with dedicated carriers, rubber-tipped tools, or vacuum tweezers; avoid direct metal-to-ceramic contact.
  3. Incompatible bonding prep → Confirm surface roughness (Ra <0.05 μm for polished sheets) before selecting adhesive or metallization route.
  4. Improper stacking → Avoid storing thin polished sheets under heavy loads; this causes micro-cracks invisible at inspection but critical during heating.
  5. Rapid temperature change → Do not quench thin sheets; preheat furnace and load gradually to prevent fracture from thermal gradient.

Alumina Ceramic Sheet FAQ

1. Q: What grades of alumina sheet do you supply?
   A: Common engineering grades include  96%, 99%, 99.5% and 99.7%  alumina; selection balances dielectric properties, hardness, and machining of edges.
2. Q: What is the price of alumina sheet?
   A: The price of an alumina sheet depends on thickness, dimensions, purity grade, and surface finish. Thin sheets such as 0.5 mm or below require precision machining and special packaging, which may increase the cost. At ADCERAX, we provide clear quotations based on drawings or size requirements, with options for both small trial batches and bulk orders.
3. Q: Can I buy a thin alumina sheet like 0.05 mm?
   A: Yes, alumina sheets as thin as 0.05 mm can be supplied, but availability depends on the required size, flatness, and edge condition. Ultra-thin sheets require special handling and protective packaging to avoid chipping or warping during transport. For precise applications, it is recommended to provide drawings with thickness tolerance and surface finish requirements so the correct production route can be confirmed.
4. Q: How to cut alumina sheet?
   A: Alumina sheets cannot be cut with standard tools because of their hardness and brittleness. The recommended methods are diamond wheel grinding, CNC machining with coolant, or laser cutting for thin sheets. Each method must control feed rate and cooling to prevent edge chipping. For tight-tolerance parts, it is best to supply drawings so cutting and finishing can be done during production rather than post-processing.
5. Q: Can I request polished alumina ceramic sheets?
   A: Single-side or double-side polishing is available; specify Ra or mirror finish if bonding or metallization is planned.
6. Q: Can you provide an alumina ceramic data sheet?
   A: Yes, a full alumina ceramic data sheet can be provided with each batch. It typically includes chemical composition, density, hardness, dielectric strength, maximum service temperature, and thermal expansion coefficient.
7. Q: Can I source alumina sheet directly from a manufacturer in China?
   A: Yes. ADCERAX is a China-based manufacturer and supplier of alumina sheets, offering both standard sizes and custom options based on drawings. By working directly with our factory, buyers gain access to competitive pricing, flexible small-batch orders, and stable supply to support long-term industrial projects.
8. Q: What is the difference between silica sheet and alumina sheet?
   A: Silica sheets are more economical and excel in thermal shock resistance, suitable for general insulation at lower temperatures. Alumina sheets deliver superior hardness, dielectric properties, and high-temperature stability, making them the preferred choice for industrial insulation, wear liners, and lab applications where performance and reliability are critical.

   Property	Silica Sheet (SiO₂)	Alumina Sheet (Al₂O₃)
   Max. Service Temperature	~1000–1200 °C	~1400–1600 °C
   Hardness	Low–medium, softer and easier to machine	High hardness (>15 GPa), wear resistant
   Thermal Shock Resistance	Excellent (withstands rapid heating/cooling)	Moderate, requires controlled heating/cooling
   Dielectric Strength	Limited, not ideal for high-voltage insulation	Strong dielectric performance, stable under heat
   Chemical Resistance	Good against acids but weaker in alkali	Stable against acids, alkalis, and most solvents
   Cost	Lower, economical for general insulation	Higher, justified by durability and performance
   Typical Applications	Furnace lining, lightweight insulation, glass industry	Electrical insulation pads, wear liners, furnace carriers, lab supports

Client Reviews about Alumina Sheet

• ⭐️⭐️⭐️⭐️⭐️
  “We purchased alumina sheet as electrical insulation pads from ADCERAX; the thickness tolerance simplified torque settings and reduced rework.”
  — Mark T., Manufacturing Engineer, Apex Drive Systems
• ⭐️⭐️⭐️⭐️⭐️
  “For wear liners, the nonporous alumina ceramic sheets kept surfaces clean in coolant; edge chamfers improved handling.”
  — Laura G., Process Supervisor, Nordic Automation
  
• ⭐️⭐️⭐️⭐️⭐️
  “The 96 alumina sheet met our bonding plan after double-side polish; drawings matched on the first lot.”
  — Kenji S., R&D Technician, Shinrai Instruments
• ⭐️⭐️⭐️⭐️⭐️
  “Quarterly replenishment of alumina sheet wholesale from ADCERAX stabilized our maintenance schedule and inventory.”
  — Daniel R., Purchasing Lead, Westport Industrial