Drilling Alkali-Free Glass: Alkali-Free Glass (CTE 3.2 x 10^-6 /K, 350 nm – 2.0 um); Drilling to +/-0.02 mm hole position. Single-piece prototypes to production volumes, quoted from your drawing.
The combination of Alkali-Free Glass and Drilling comes up constantly in RFQs for a reason – the material offers display-grade surface quality, and Drilling is the right way to get accurate geometry into it. Expect +/-0.02 mm hole position and exit-chip controlled below 0.1 mm.
The numbers
| Material | Alkali-Free Glass (AF32 / EAGLE-class display glass) |
|---|---|
| Thermal expansion (CTE) | 3.2 x 10^-6 /K |
| Service temperature | 600 C (Tg 717 C) |
| Transmission range | 350 nm – 2.0 um |
| Density | 2.43 g/cm3 |
| Knoop hardness | 590 kg/mm2 |
| Refractive index | 1.51 @ 587 nm |
| Stock thickness | 0.10 – 1.1 mm |
| Maximum blank size | 400 x 300 mm |
| Process | Drilling |
| Working tolerance | +/-0.02 mm hole position |
| Minimum feature | 0.15 mm laser / 0.5 mm mechanical |
| Surface finish | exit-chip controlled below 0.1 mm |
| Thickness window | 0.1 – 30 mm |
| Edge condition | optional chamfered hole entry |
| RFQ inputs | PDF/DXF/STEP drawing, quantity brackets, surface and edge spec |
Specification advice
The shop-floor rules that matter here:
- Material note: thin sheets below 0.3 mm demand carrier-supported handling through every step.
- Process boundary: hole-to-edge distance should stay above 1.5x thickness to protect strength.
- Over-specification is the quiet budget killer: a 20/10 scratch-dig face costs roughly three times an 80/50 face, so grade each surface individually.
For the complete framework, see the tolerance design guide and the holes and edges design guide.
Capabilities and limits
The core strength of Drilling is through-holes, blind holes and countersinks at densities beyond 1,000 holes per part. The honest limit: hole-to-edge distance should stay above 1.5x thickness to protect strength. Both belong on the drawing before quoting, not after.
One material, many routes: on Alkali-Free Glass we also quote etching, grinding, laser cutting, lapping, and multi-step drawings are the norm rather than the exception.
Typical applications
Orders for drilling alkali-free glass cluster in oled packaging (cover lids, frit-seal frames, fill-port plates); industrial displays (touch covers, gauge windows, printed bezels); ccd inspection equipment (CCD cover plates, reference grids, stage glass). Background reading on the underlying material science: SCHOTT AF 32 eco.
The fastest route to a quote is geometry: use the 3D configurator below, or the site-wide custom glass machining 3D builder for fully custom parts.
Related reading on this site: alkali-free glass wafers, precision glass drilling, material selection guide.
Common questions
What tolerances are achievable on Alkali-Free Glass parts?
Ground features hold +/-0.01 mm and lapped thickness reaches +/-0.003 mm. Thin sheets below 0.3 mm demand carrier-supported handling through every step.
What thickness range do you stock for Alkali-Free Glass?
Standard stock spans 0.10 – 1.1 mm, with blanks up to 400 x 300 mm. Other formats are sourced per order.
How does Alkali-Free Glass behave under heat?
CTE is 3.2 x 10^-6 /K and continuous service reaches 600 C (Tg 717 C), which is what drives its use where no alkali ion migration into TFT or sensor layers matters.
What accuracy does drilling hold?
+/-0.02 mm hole position with minimum features of 0.15 mm laser / 0.5 mm mechanical. Hole-to-edge distance should stay above 1.5x thickness to protect strength.
What equipment runs the drilling work?
Diamond core drills, ultrasonic assist and laser percussion heads.
Specifications on this page were last reviewed by our engineering team in July 2026.