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Borosilicate glass is used in all those applications where there is a need to observe something without touching it or as a protection, so for low-pressure sight windows and machinery protections glass. Owing to its high technical resistance, (around 490°C) it can also be used for gas stoves, wall boilers, electric ovens, etc. Borosilicate glass is supplied in sheets or rings in accordance with customer specifications

Technical features

• Max T°: 490°C (for short periods of time only)
• Operating T°: 230°C
• Max ∆ T: 130°C

Physical properties

• Specific gravity, g/cm3: 2,23
• Refractive index nd: 1,474
• Coefficient of thermal expansion:
32,5 x 10-7x K-1
• Young's module, Kg/mm2: 6400
• Poisson coefficient: 0,20
• Knoop Hardness, KHN 100: 418
• Alternate flexure ultimate tensile strength (25°C), N/mm2: 49 (corresponding to Kg/mm2: 4,9)


2,75 mm ±0,3 mm

3,3 mm ±0,3 mm

5 mm ±0,2 mm

6,5 mm ±0,2 mm

9 mm ±0,3 mm

11 mm ±0,3 mm

15 mm ±0,3 mm

20 mm ±0,3 mm

Other thicknesses upon request


Impact resistance

Resistance to impact of borosilicate glass is dependant on assembly conditions, glass size, shape and thickness, and type of mechanical stress as well as other parameters. Therefore, resistance indications are to be verified for each specific case, in accordance with the required specifications and actual circumstances.