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SPECIALGLASS supplies high alumino-silicate ultra-thin glass for the most demanding cover-glass programs — premium phones, tablets, and automotive glazing. Pushing Al₂O₃ higher raises ion-exchange efficiency, so the glass reaches greater strengthened hardness (700 HV after strengthening) and the mechanical margin that high-end devices are specified against. Offered in high-alumino-silicate and lithium-alumino-silicate grades from 0.33 mm to 6 mm, cut to your drawing.
Not every program needs the same strengthening response, so the glass comes in two chemistries. The high-alumino-silicate grade carries elevated Al₂O₃ for strong ion exchange and reaches 700 HV after strengthening — the workhorse for premium phone, tablet, and automotive cover glass. The lithium-alumino-silicate grade adds lithium to the network for the highest strengthening response, reserved for the toughest cover-glass duty. Both are ion-exchangeable ultra-thin stock built to survive drop and scratch in the field.
A high softening point (830 °C) and controlled CTE let this glass hold shape through aggressive strengthening and downstream processing. The constants below define how it behaves on the line.
| Property | Unit | Value |
|---|---|---|
| Density | g/cm³ | 2.47 |
| CTE | ×10⁻⁷/°C | 98 |
| Softening point | °C | 830 |
| Annealing point | °C | 606 |
| Strain point | °C | 558 |
| Young’s modulus | GPa | 75.6 |
| Poisson’s ratio | — | 0.23 |
| Vickers hardness (strengthened) | HV | 700 |
| Refractive index | — | 1.51 |
| Photoelastic coefficient | nm/cm/MPa | 27.2 |
The same temperature-differential discipline applies here: preheat, strengthening, and anneal stages are held within a 50 °C spread to protect thin glass from warp and thermal shock. The longer strengthening dwell reflects the higher Al₂O₃ chemistry, which exchanges ions more aggressively for a harder, more drop-resistant surface.
| Stage | Temp (°C) | Interval | Duration (min) |
|---|---|---|---|
| Preheat | 380 | T0–T1 | 60–90 |
| T1–T2 | 15 | ||
| Strengthen | 400–420 | T2–T3 | 180–300 |
| T3–T4 | 5 | ||
| Anneal | 380 | T4–T5 | 150 |
Supplied on the standard G5 sheet or cut to drawing, across a thickness range wide enough to cover thin phone cover glass through thicker automotive and structural formats.
Wherever a thin surface has to take repeated impact and stay clear, this glass is specified in:
Send dimensioned drawings (DWG/DXF/PDF) with thickness, quantity, and edge requirement, and our team will quote your glass cutting project.