High Hardness Glass · Sapphire (Single Crystal)
Sapphire
Sapphire is a high hardness glass glass — single-crystal optical sapphire. Typical values: 400 MPa yield, 3.98 g/cm³, rated to 1,800 °C. Available for CNC machining, Sheet metal at FabDigit.
Properties
Typical room-temperature values in the Annealed Glass condition. Metric first, imperial in gray. The bars show where Sapphire sits against the other 8 glass grades in the catalog.
Datasheet
| Yield strength | 400 MPa58 ksi |
|---|---|
| Tensile strength | 400 MPa58 ksi |
| Hardness | 2200 HV≈ 2090 HB |
| Density | 3.98 g/cm³0.144 lb/in³ |
| Specific strength (yield ÷ density) | 101 |
| Min service temp | -200 °C-328 °F |
| Max service temp | 1,800 °C3,272 °F |
| Electrical conductivity | < 0.001 % IACSinsulator |
| Machinability | Poor20 / 100 |
| Weldability | Not recommended5 / 100 |
| Formability | Not recommended5 / 100 |
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Against other glass grades
Strength versus weight in the glass family
Yield strength against density for every glass grade FabDigit runs. Sapphire is highlighted; hover a dot for its name, or open the interactive family chart.
Manufacturability
The process limits FabDigit's quote engine applies to Sapphire. Design inside these and the part quotes instantly; outside them it routes to an engineer.
CNC machining
| Machinability | Poor20 / 100 |
|---|---|
| Cutting speed (rough / finish) | — / — |
| Minimum wall | — |
| Minimum internal radius | — |
| Drill depth limit | — |
| Best surface (machined / polished) | Ra — / — |
| Hardenable after machining | — |
Sheet metal
| Formability | Not Recommend5 / 100 |
|---|---|
| Weldability | Not Recommend5 / 100 |
Conditions and tempers
How Sapphire is supplied and what each state is for. The default is what FabDigit quotes unless your drawing says otherwise.
| Condition | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Annealed GlassDefault Heat Treat State | Standard glass — can still be cut and drilled to size | — | — | — | — |
Heat treatment and post-processing
Operations FabDigit's suppliers routinely run on Sapphire, ranked by how often they make sense for this grade.
Post-processing
| Manual Deburr | Deburrstandard |
|---|---|
| Edge Break (0.5mm) | Deburr |
| CMM Inspection | Inspection |
| FAI Report | Inspection |
| Individual Bag | Packaging |
Surface finishes for Sapphire
Coatings and treatments compatible with glass on the processes Sapphire runs on. Pick them in the quote configurator or call them out on the drawing.
Marking / Decoration
- Chemical Etching
- Dot Peen Marking
- Electro-chemical Etching
- Embossing / Debossing
- Ink Stamping
- Laser Marking
- Mechanical Engraving
- Vibro Engraving / Scribing
Equivalent designations
Standards and trade names that resolve to Sapphire in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- Sapphire WindowC-Plane Sapphire
- Other
- Single Crystal Al2O3
Stock forms
Raw-material forms FabDigit sources Sapphire in.
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.