Conical Zirconia Crucible for High-Temperature Furnace and Reactor Integration

Addressing Critical Industrial Needs with ADCERAX® Conical Zirconia Crucible

• Conical Zirconia Crucible in Vacuum Melting Furnaces

  ✅Key Advantages

  1. Ultra-low Porosity Barrier + The ≤0.5% apparent porosity and ≥4.5 g/cm³ bulk density limit gas pathways into the melt. These values curb oxygen ingress and suppress crucible erosion at high temperature.
  2. High-Temperature Integrity + Continuous service up to 2200 °C maintains wall cohesion during long holds. A 9–11 × 10⁻⁶/K thermal expansion window supports repeated heat-cool cycles without microcracking.
  3. Clean Chemistry Matrix + ZrO₂ ≥92% with Fe₂O₃ ≤0.5% minimizes extraneous oxide sources. Low SiO₂ (≤0.5%) reduces silica pickup in nickel- and cobalt-base alloys.

  ✅ ️Problem Solved

  A vacuum melting line targeting high-purity superalloys switched to ADCERAX® Conical Zirconia Crucible to control melt cleanliness. With ≤0.5% porosity and ≥4.5 g/cm³ density, the crucible eliminated the porous pathways that previously seeded oxygen spikes. ZrO₂ ≥92% and Fe₂O₃ ≤0.5% kept oxide contribution below internal control limits across multi-heat campaigns. At 2000–2150 °C, wall integrity was maintained, reducing unplanned stops tied to crucible wear. Melt chemistries stayed within control charts while cycle cadence remained unchanged.

• Conical Zirconia Crucible in Controlled Atmosphere Reactors

  ✅Key Advantages

  1. Inert Under Reactive Gases + ZrO₂ ≥92% and Fe₂O₃ ≤0.5% resist oxidation-reduction interactions. Chemistry stability holds in CO/CO₂, H₂/N₂, and O₂-rich conditions.
  2. Dense, Leak-Resistant Body + ≤0.5% apparent porosity limits gas permeation through the wall. The dense microstructure sustains barrier function during extended residence times.
  3. Mechanical Stability at Heat + Flexural strength ≥350 MPa and CTE 9–11 × 10⁻⁶/K support thermal cycling above 2000 °C. Structural integrity prevents crack-initiated leaks that distort reactor data.

  ✅ ️Problem Solved

  A lab reactor program alternating oxidizing and reducing steps at >2000 °C reported inconsistent results due to crucible reactivity and hairline leaks. Deploying ADCERAX® Conical Zirconia Crucible (ZrO₂ ≥92%, porosity ≤0.5%) stabilized the containment boundary and removed a known contamination vector. Flexural strength ≥350 MPa sustained repeated ramps without crack initiation. Across sequential runs, gas composition readings and product analyses held within method tolerances, and downtime from vessel replacement was avoided.

• Conical Zirconia Crucible in Energy-Efficient Induction Furnaces

  ✅Key Advantages

  1. Arc Geometry Heat Coupling + Curved walls align with semi-cylindrical coil profiles to reduce hot-spot formation. Better geometric coupling supports uniform wall heat flux at set power.
  2. Thermal Cycling Endurance + CTE 9–11 × 10⁻⁶/K with ≥350 MPa flexural strength resists shape drift under alternating loads. Stability preserves coil-to-load efficiency over repeated starts.
  3. Controlled Heat Leakage + Thermal conductivity 2.5–3.0 W/m·K limits lateral losses at high temperature. Stable ≥4.5 g/cm³ density maintains consistent thermal response during long holds.

  ✅ ️Problem Solved

  An induction furnace with semi-cylindrical coils experienced uneven wall temperatures and elevated power draw when using cylindrical vessels. The ADCERAX® Conical Zirconia Crucible matched the coil curvature, removing the geometric mismatch that created hot spots. With CTE 9–11 × 10⁻⁶/K and ≥350 MPa strength, the crucible held shape through frequent ramp cycles, preserving coupling. Low conductivity (2.5–3.0 W/m·K) and dense walls reduced side losses, stabilizing the heat field at target setpoints. Operators achieved consistent thermal profiles without increasing input power.

User Guide for Conical Zirconia Crucible

The Conical Zirconia Crucible requires disciplined setup, operation, and care to achieve stable thermal distribution and long service life. This guide summarizes essential practices for furnaces and reactors so engineers can run the Arc Shaped Zirconia Crucible safely, cleanly, and efficiently.

• Pre-Conditioning and Furnace Setup

  1. Dry-Out Before First Use — Pre-bake at 105 °C for 120 minutes to remove moisture. Moisture trapped in walls can flash to steam at heat. Controlled dry-out reduces crack initiation.
  2. Seat and Spacers — Do not place the crucible directly on the hearth. Elevate with alumina spacers to promote airflow and reduce thermal gradients. This improves uniform heating of the arc wall.
  3. Clearance from Heaters — Keep a gap > 2 cm from SiC/SiMo elements or coils. Adequate spacing limits radiant hot spots. It also reduces localized thermal stress.

• Loading, Heating, and Cooling Practices

  1. Charge Preparation — De-oil and dry metallic charge before loading. Residual volatiles raise internal pressure during heat. Clean charge reduces spatter and wall attack.
  2. Fill Strategy — Do not overpack; leave expansion headspace. Crowded feed can wedge the wall during thermal growth. Even distribution supports stable pooling.
  3. Ramp Rates — Use ≤ 5 °C/min below 1200 °C and ≤ 4 °C/min above 1200 °C. Moderate ramps minimize thermal shock. Hold steps help equalize wall and melt temperatures.

• Handling, Removal, and Personal Safety

  1. PPE Discipline — Wear heat-rated gloves, face shield or goggles, and protective clothing. High radiant heat persists after power off. Treat fixtures and tongs as hot.
  2. Metal Removal — Prefer ladling to empty molten metal. Minimize tong clamping that loads a small area. If tongs are required, use arc-matched jaws.
  3. In-Process Checks — Visually inspect for new surface crazing each cycle. Stop if cracks, spalls, or glaze blisters appear. Continued use with defects risks sudden failure.

• Cleaning, Storage, and Service Life Management

  1. Post-Run Cleaning — Let the crucible cool to a safe handling temperature. Remove residues with non-metallic scrapers and lint-free wipes. Avoid aggressive acids that could alter the surface.
  2. Surface Care — Keep inner walls smooth to limit adhesion in future melts. Do not sandblast the arc surface. Gentle mechanical cleaning preserves density and finish.
  3. Storage Conditions — Store dry and ventilated away from corrosives. Use separators to prevent rubbing and scratches. Re-dry before reuse if humidity exposure occurred.

FAQs about Conical Zirconia Crucible

1. Q: How does the Conical Zirconia Crucible limit contamination in vacuum melts?
   A: The Conical Zirconia Crucible uses a dense body (apparent porosity ≤0.5%, bulk density ≥4.5 g/cm³) to block oxygen ingress and metal infiltration. ZrO₂ ≥92% with Fe₂O₃ ≤0.5% lowers extraneous oxide pickup. The smooth interior reduces inclusion sites during long holds at 2000–2150 °C. Users see tighter chemistry control and fewer rejected heats.
2. Q: Is the Conical Zirconia Crucible stable in oxidizing and reducing atmospheres?
   A: Yes. The Conical Zirconia Crucible maintains chemical inertness in O₂-rich, CO/CO₂, and H₂/N₂ atmospheres. High ZrO₂ purity and low impurity indices resist gas-phase reactions at temperature. This preserves reactor baselines and repeatability across multi-step sequences.
3. Q: How does the Conical Zirconia Crucible handle thermal shock and cycling?
   A: A CTE of 9–11 × 10⁻⁶/K and flexural strength ≥350 MPa support repeated ramps. Follow ≤5 °C/min below 1200 °C and ≤4 °C/min above 1200 °C to minimize gradients. The curved wall distributes stress uniformly during heat-up and cool-down. This lowers crack initiation risk over many cycles.
4. Q: What temperature capability does the Conical Zirconia Crucible provide?
   A: The Conical Zirconia Crucible supports continuous service up to 2200 °C. Wall cohesion is maintained during extended dwells typical of alloy refining and synthesis. Low thermal conductivity (≈2.5–3.0 W/m·K at 1000 °C) moderates lateral losses. Users achieve stable setpoints with fewer power adjustments.
5. Q: How does the arc geometry improve induction furnace efficiency?
   A: The Conical Zirconia Crucible aligns with semi-cylindrical coils to reduce hot-spot formation. Better geometric coupling smooths wall heat flux at a given power input. Field use often shows 8–12% energy reduction at equal throughput. IR maps confirm a lower ΔT across the hot zone.

Client Experiences with ADCERAX® Conical Zirconia Crucible

• ⭐️⭐️⭐️⭐️⭐️
  “Switching to the Conical Zirconia Crucible eliminated oxygen spikes in our vacuum melts. Off-spec heat rate fell from 7.8% to 1.6% over 3 months. We held 2100 °C for 6-hour dwells across 12 cycles without wall erosion.”
  – J. Müller, Process Engineer | A* Alloys GmbH (DE)
• ⭐️⭐️⭐️⭐️⭐️
  “In our H₂/N₂ ↔ O₂ cycling reactor, the Conical Zirconia Crucible stopped micro-leaks that distorted results. GC baselines stayed within ±2% across 50 runs at >2000 °C. No visible crazing, and post-run residues were minimal.”
  – K. Tanaka, Lab Manager | S**** Materials Institute (JP)
• ⭐️⭐️⭐️⭐️⭐️
  “Induction coil coupling improved once we adopted the Conical Zirconia Crucible. IR mapping showed hot-spot ΔT drop from ~80 °C to ~22 °C, and energy use declined 9–12% at the same throughput. Melt surfaces were cleaner between heats.”
  – M. Rivera, Operations Lead | N*** Foundry Systems (US)
• ⭐️⭐️⭐️⭐️⭐️
  “For high-temperature synthesis, the Conical Zirconia Crucible gave stable thermal profiles and clean recovery. Our replacement interval extended from ~20 to ~45 cycles. Cleaning time per run fell by ~30%, which helped our weekly schedule.”
  – H. Schmidt, R&D Supervisor | T** Advanced Ceramics Lab (DE)**