Soda-Lime Glass FT (Fully tempered / toughened)
Heat-treated state
ASTM C1036 · EN 572 · GB 11614
Air-quenched safety glass with ≥69 MPa surface compression — pick for impact/thermal-shock duty and safety glazing; all cutting and drilling must be finished before tempering.
Values for the FT condition
Other Soda-Lime Glass tempers and conditions
Soda-Lime Glass is listed in 4 conditions; see the grade overview at Soda-Lime Glass.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ANNDefault Annealed | Standard as-drawn/float annealed glass — pick when the part must still be cut, drilled, edged or ground after supply. | — | 45 | 0 | 550 HV | 1 W/m·K |
Heat-strengthened | Roughly double annealed strength with low residual stress; chosen where flatness and non-dicing fracture pattern matter more than impact safety rating. | — | 85 | 0 | 550 HV | 1 W/m·K |
FTThis page Fully tempered / toughened | Air-quenched safety glass with ≥69 MPa surface compression — pick for impact/thermal-shock duty and safety glazing; all cutting and drilling must be finished before tempering. | — | 150 | 0 | 550 HV | 1 W/m·K |
Chemically strengthened | K⁺-for-Na⁺ ion exchange in molten KNO₃ gives a thin very high compression layer — used for thin (<3 mm) covers and instrument glass where thermal tempering is impossible. | — | 250 | 0 | 590 HV | 1 W/m·K |
What is Soda-Lime Glass FT?
Soda-Lime Glass FT is Soda-Lime Glass heat treated to FT — air-quenched safety glass with ≥69 MPa surface compression — pick for impact/thermal-shock duty and safety glazing; all cutting and drilling must be finished before tempering. Soda-Lime Glass FT has a tensile strength of 150 MPa (21.8 ksi), stronger than 87% of glass grades. Elongation at break is 0% and the elastic modulus is 72 GPa (10.4 Msi). Soda-Lime Glass FT has a density of 2.5 g/cm³ (0.0903 lb/in³), lighter than 74% of glass grades. ANN is the default condition FabDigit quotes; FT is available on request or by drawing note.
Advantages
- Low embodied carbon — 1.2 kg CO₂/kg, better than 99% of glass grades
Limitations
- Difficult to machine — 2/100, worse than 98% of glass grades
- Limited service temperature — 250°C (482 °F), worse than 83% of glass grades
- Poor heat conductor — 1 W/m·K (0.578 BTU/hr·ft·°F), worse than 77% of glass grades
Soda-Lime Glass FT properties
Typical room-temperature values for Soda-Lime Glass FT; 11 are specific to this condition. Other listed values are Soda-Lime Glass reference data and may not represent this condition. Bars are the position among glass grades.
Physical4
Soda-Lime Glass FT has a density of 2.5 g/cm³ (0.0903 lb/in³), lighter than 74% of glass grades.
Mechanical12
Soda-Lime Glass FT has a tensile strength of 150 MPa (21.8 ksi), stronger than 87% of glass grades. Elongation at break is 0% and the elastic modulus is 72 GPa (10.4 Msi).
Thermal5
Soda-Lime Glass FT is rated for continuous service to 250°C (482 °F). It conducts heat at 1 W/m·K (0.578 BTU/hr·ft·°F), worse than 77% of glass grades. Thermal expansion is 9 µm/m·K (5 µin/in·°F).
Electrical5
Soda-Lime Glass FT is an electrical insulator with a dielectric strength of 12 kV/mm (304.8 V/mil) and a resistivity of 1×10¹⁰ Ω·m.
Chemical & Environmental2
Corrosion resistance is excellent (85/100), better than 65% of glass grades.
Sustainability4
Producing a kilogram of Soda-Lime Glass FT takes about 15 MJ of energy and emits 1.2 kg of CO₂ — less than 99% of glass grades. Typical recycled content is 22%.
Manufacturability2
Soda-Lime Glass FT's machinability is not recommended (2/100, worse than 98% of glass grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Soda-Lime Glass FT
Is Soda-Lime Glass easy to machine?
Score-and-snap with a carbide/diamond wheel; holes and edges need diamond core drills and wet grinding, and all machining must precede tempering.
Can Soda-Lime Glass be welded?
Not weldable in the metallic sense — joined by flame/laser fusion sealing to matched-CTE glass, glass frit, or adhesive/gasket bonding.
Can Soda-Lime Glass be formed, bent or molded?
Formed above the softening point (~720 °C) by float, press, blow or slumping; anneal through 545–505 °C to remove residual stress.
What surface finishes work on Soda-Lime Glass?
Ground and cerium-oxide polished edges, acid-etch or sandblast for satin finish, and magnetron-sputtered low-E, mirror or AR coatings adhere well.
Soda-Lime Glass chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Na2Ofrom soda ash, flux | 12 – 16 | 13.8 |
| CaOfrom limestone, stabiliser | 5 – 12 | 8.8 |
| MgOfrom dolomite | 0 – 5 | 3.9 |
| Al2O3improves durability | 0.3 – 2.5 | 1 |
| K2O | 0 – 1 | 0.3 |
| SO3refining residue | 0.1 – 0.4 | 0.2 |
| Fe2O3≤0.02 % for low-iron/extra-clear grades | 0.02 – 0.15 | 0.08 |
| SiO2network former | ≥ 69 (balance) | — |
Soda-Lime Glass FT — frequently asked
What is Soda-Lime Glass FT used for?
Soda-Lime Glass FT is typically used for window/architectural glazing, bottles and jars, automotive glass and mirrors. In short: lowest-cost silicate glass; highest-volume flat glass; temperable and chemically strengthenable.
What is the tensile strength of Soda-Lime Glass FT?
Soda-Lime Glass FT has a typical tensile strength of 150 MPa (21.8 ksi) — stronger than 87% of glass grades. Strength varies by condition: see the 4 listed tempers.
Is Soda-Lime Glass FT easy to machine?
Not especially — machinability is rated not recommended (2/100, worse than 98% of glass grades). Score-and-snap with a carbide/diamond wheel; holes and edges need diamond core drills and wet grinding, and all machining must precede tempering.
Can Soda-Lime Glass FT be welded?
Not weldable in the metallic sense — joined by flame/laser fusion sealing to matched-CTE glass, glass frit, or adhesive/gasket bonding.
What surface finishes work on Soda-Lime Glass FT?
Ground and cerium-oxide polished edges, acid-etch or sandblast for satin finish, and magnetron-sputtered low-E, mirror or AR coatings adhere well.
Can Soda-Lime Glass FT be formed, bent or molded?
Formed above the softening point (~720 °C) by float, press, blow or slumping; anneal through 545–505 °C to remove residual stress.
What is the maximum service temperature of Soda-Lime Glass FT?
Soda-Lime Glass FT is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- ASTM C1036 — Standard Specification for Flat Glass — ASTM International (2021)
- ASTM C1048 — Heat-Strengthened and Fully Tempered Flat Glass — ASTM International (2018)
- EN 572-1 — Glass in building: basic soda lime silicate glass products, definitions and general properties — CEN (2012)
- IEC 60672-3 — Ceramic and glass insulating materials, Part 3: Specifications for individual materials (Types G-110/G-120) — IEC (1997)
- ASM Engineered Materials Handbook Vol.4: Ceramics and Glasses — ASM International (1991)
- Float glass technical data (clear soda-lime, 3–19 mm) — Schott / Saint-Gobain / (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.