Custom Machinable Glass Ceramic Parts – CNC-Machined Complex Shapes and Cavities

Machinable Glass Ceramic Parts – Application Scenarios

• Vacuum and Analytical Equipment Components

  ✅Key Advantages

  1. High-temperature vacuum insulation
  Machinable glass ceramic parts provide structural insulation in chambers and feedthrough regions where components see up to around 800 °C and must maintain low outgassing under vacuum or controlled atmosphere.

  2. Stable geometry without post-firing
  Because the material is used in its final state, machined features on vacuum flanges, spacer blocks and carriers maintain dimensional stability during bake-out and repeated thermal cycles within the recommended temperature window.

  3. Electrical isolation at voltage
  Machinable glass ceramic parts can act as insulator standoffs, coil supports and barrier plates in vacuum assemblies, with dielectric strength on the order of tens of kilovolts per millimetre.

  ✅ Problem Solved

  A vacuum system builder needs insulating support blocks for internal hardware operating at high voltage and elevated temperature. Metal supports create leakage paths, and polymer supports cannot survive bake-out near 200–250 °C. By switching to machinable glass ceramic parts with dielectric strength around 45 kV/mm and continuous use temperature near 800 °C, the builder can run higher bake temperatures and higher bias voltages without redesigning the chamber, while keeping machining lead time closer to that for metal parts.

• Photonics, Laser and Optical Assemblies

  ✅Key Advantages

  1. Precision mounts with controlled expansion
  Machinable glass ceramic parts used as spacers, carriers and mounting plates offer thermal expansion close to many sealing glasses and metals, which helps maintain alignment in optical benches and laser cavities.

  2. Complex features from CNC machining
  Tapped holes, slots, pockets and recesses for mirrors, lenses and fibre ferrules can be machined directly into the ceramic without mould tools or post-sintering, supporting iterative development and low-volume series assemblies.

  3. Electrical and thermal isolation in one part
  A single machinable glass ceramic part can act as both a mechanical mount and an insulating barrier near high-voltage drivers or elevated temperature zones within photonics modules.

  ✅ Problem Solved

  An OEM laser system requires a combined mechanical and electrical interface block between a high-power laser head and a cooled metal chassis. Previous metal blocks needed multiple additional insulators and shims to separate live conductors from ground. By redesigning the interface as a single machinable glass ceramic part with integrated mounting faces, countersinks and clearances, the assembly reduces part count, improves creepage distance and maintains alignment through thermal cycles driven by laser duty cycles.

• Thermal Processing Jigs and Fixtures

  ✅Key Advantages

  1. Structural support at elevated temperature
  Machinable glass ceramic parts can hold components, carriers or sensors in position in ovens and furnaces operating up to approximately 800 °C, providing rigid support where polymers and most engineering plastics are not usable.

  2. Low thermal conductivity for local isolation
  The relatively low thermal conductivity of machinable glass ceramic helps build localized heat breaks in fixture arms and supports, limiting heat flow into bearings, frames or measurement hardware.

  3. Geometry tailored to process flow
  Slots, recesses and guiding surfaces can be machined into the ceramic to support parts in a repeatable orientation, which improves consistency in thermal cycles and process quality.

  ✅ Problem Solved

  A manufacturer of sensor housings needs repeatable fixturing for a thermal cure step around 500–600 °C. Metal fixtures cause temperature gradients and unwanted heat leakage into handling hardware, while refractory bricks cannot be shaped accurately. By using machinable glass ceramic parts with machined nests and stops, the OEM can achieve consistent part positioning, better temperature uniformity and reduced rework, while keeping fixture weight and adjustment effort manageable.

Machinable Glass Ceramic Parts – Use Guide

• Installation

  1. Verify that mating metal parts are deburred and free from sharp burrs or raised edges to avoid point loading on machinable glass ceramic parts.
  2. Use flat washers or load-spreading pads where bolts clamp directly onto ceramic surfaces.
  3. Avoid overtightening fasteners; set torque levels appropriate for brittle materials and, where possible, test on sample parts before final assembly.

• Use

  1. Keep operating temperatures within the proven range for machinable glass ceramic parts, typically up to 800 °C for continuous use and peak temperatures near 1000 °C without mechanical load.
  2. Limit rapid temperature changes; preheat assemblies gradually and avoid exposing only one side of a thick part to sudden heating or cooling.
  3. In vacuum and controlled atmospheres, follow an agreed bake-out schedule so that outgassing is minimized before the ceramic is placed near sensitive detectors or optics.

• Storage

  1. Store machinable glass ceramic parts in padded trays or boxes with separators between parts to reduce the chance of chipping.
  2. Keep parts in a dry, clean area away from abrasive dust or loose metal chips.
  3. Maintain labels and drawing references with each batch so that orientation and critical faces remain traceable for installation.

• Cleaning

  Before vacuum or optical use, clean machinable glass ceramic parts with suitable solvents or detergents and deionized water, then dry completely; avoid leaving lint or particles on sealing or alignment surfaces.
  For high-vacuum service, complete a controlled bake-out step after cleaning to remove residual moisture and surface volatiles.

• Precautions and Typical Misuse Scenarios

  1. Issue: Cracking after rapid thermal cycling
  Symptom: A machinable glass ceramic part develops cracks or chips after repeated rapid heating and cooling.
  Likely cause: Thermal gradients exceed the material’s shock resistance.
  Mitigation: Reduce ramp rates, increase soak time for uniform temperature and redesign to reduce thick-to-thin transitions and sharp internal corners.

  2. Issue: Edge chipping during assembly
  Symptom: Small chips appear on edges or hole entrances when machined parts are installed.
  Likely cause: Hard contact with metal tooling or over-tightened fasteners.
  Mitigation: Use alignment pins or soft jaw tooling during installation and apply torque in steps while monitoring for movement or sound changes.

  3. Issue: Unexpected tracking or arcing at high voltage
  Symptom: Localized discharge paths across the surface of machinable glass ceramic parts under high voltage.
  Likely cause: Surface contamination films, inadequate creepage distance or unintended sharp points.
  Mitigation: Improve cleaning, round sharp edges in high-field regions and increase spacing or add shields along the path between conductors.

 Machinable Glass Ceramic Parts FAQ

1. Q: What is the maximum operating temperature of machinable glass ceramic parts?
   A: Machinable glass ceramic parts based on Macor-type materials typically operate continuously around 800 °C, with short-term peak temperatures up to about 1000 °C when not under mechanical load.
2. Q: Can machinable glass ceramic parts be used in high or ultra-high vacuum systems?
   A: Yes, machinable glass ceramic parts are widely used as supports and insulators in vacuum equipment because the material has zero or near-zero open porosity and, when baked properly, shows very low outgassing.
3. Q: How do machinable glass ceramic parts compare with fully sintered alumina components?
   A: Machinable glass ceramic parts are easier to machine into complex 3D shapes and do not require post-sinter shrinkage allowances, but fully sintered alumina generally offers higher hardness and better wear resistance; the choice depends on whether geometry flexibility or wear resistance is more important.
4. Q: What part sizes are practical for machinable glass ceramic machining?
   A: Standard slab and rod sizes cover a range from small blanks for compact parts up to larger plates and blocks that can be machined into sizeable fixtures; practical limits depend on available stock dimensions and the stiffness required in the final machinable glass ceramic part.
5. Q: What information should be included on drawings for machinable glass ceramic parts?
   A: Drawings for machinable glass ceramic parts should define all critical dimensions and tolerances, reference faces, hole details, thread specifications, surface finish on sealing or optical areas, and any special notes on temperature, atmosphere or electrical isolation requirements.

Machinable Glass Ceramic Parts Reviews

• ⭐️⭐️⭐️⭐️⭐️
  We use ADCERAX machinable glass ceramic parts as insulating blocks and spacers in several vacuum platforms. The parts match our drawings, the dimensions are consistent from batch to batch and the material behaves predictably during bake-out.
  --Michael R., Operations Manager, North Coast Vacuum Systems
• ⭐️⭐️⭐️⭐️⭐️
  Our team relies on custom machinable glass ceramic components for laser cavity mounts and alignment fixtures. The ability to integrate threaded holes and pockets in one part has reduced assembly steps without compromising stability at temperature.
  -- Laura S., Engineering Director, OptiBeam Technologies
• ⭐️⭐️⭐️⭐️⭐️
  ADCERAX is now our preferred factory supplier for machined glass ceramic parts. Pricing is competitive for European projects, but more important for us is that the tolerances and inspection reports line up with our high-mix production needs.
  -- Daniel K., Purchasing Manager, EuroTherm Process Equipment GmbH
• ⭐️⭐️⭐️⭐️⭐️
  We worked with ADCERAX on a set of custom machinable glass ceramic parts for a new analytical instrument. The engineering support on edge details and wall thickness helped us avoid cracking in early prototypes and accelerated our design release.
  -- Kei W., Senior Mechanical Engineer, Advanced Instrumentation Labs