Chemical Strengthening Alkali-Free Glass: Alkali-Free Glass (CTE 3.2 x 10^-6 /K, 350 nm – 2.0 um); CS > 600 MPa, DoL 8 – 40 um. Single-piece prototypes to production volumes, quoted from your drawing.
chemical strengthening alkali-free glass is potassium ion exchange applied by KNO3 salt bath, 380 – 450 C. On Alkali-Free Glass it 4 – 8x bend strength on thin covers – the specification we run to is CS > 600 MPa, DoL 8 – 40 um.
Specifications at a glance
| 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 |
| Treatment | Chemical Strengthening – potassium ion exchange |
| Specification | CS > 600 MPa, DoL 8 – 40 um |
| Deposition / method | KNO3 salt bath, 380 – 450 C |
| RFQ inputs | PDF/DXF/STEP drawing, quantity brackets, surface and edge spec |
Manufacturing capability
One material, many routes: on Alkali-Free Glass we also quote polishing, etching, lapping, laser cutting, and multi-step drawings are the norm rather than the exception.
Specification advice
Before sending the RFQ, check these against your drawing:
- Material note: thin sheets below 0.3 mm demand carrier-supported handling through every step.
- Sequence matters: all machining happens before chemical strengthening; post-coating rework is not economical.
- 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.
Typical applications
The recurring buyers of chemical strengthening alkali-free glass: 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 builder below, draw a dimensioned 2D drawing from it, or open the site-wide custom glass machining 3D + 2D builder for fully custom parts.
Related reading on this site: alkali-free display glass, alkali-free glass wafers, infrared windows.
Common questions
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 does chemical strengthening add?
4 – 8x bend strength on thin covers. Applied by KNO3 salt bath, 380 – 450 C to CS > 600 MPa, DoL 8 – 40 um.
Is there a minimum order for chemical strengthening alkali-free glass?
No. Single prototypes are accepted, and pricing steps down at 10, 100 and 1,000 pieces.
How fast can prototypes ship?
Machined prototypes ship in 5 – 10 working days. Coated or bonded parts add 1 – 2 weeks depending on queue slots.
What files do you need for a quote?
A dimensioned PDF plus DXF or STEP geometry. If only a sketch exists, our drawing review service formalizes it before quoting.
Specifications on this page were last reviewed by our engineering team in August 2026.