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Heat Stregthened: Performance


  • Heat-strengthened glass:
    • is more resistant to thermal stress than annealed glass. It can withstand differences in temperature of approximately 100°C
    • more resistant to breakage due to bending (70 N/mm²) than annealed glass
    • breaks into large sharp pieces which can cause injury

    Accordingly, heat-strengthened glasses are not safety glasses. Heat-strengthened glasses break in a crazed pattern.

  • Magnetron coatings which can be thermally treated must be heat strengthened to achieve the stated performance (fragmentation, optical, Ug value)
  • The light, thermal and energy performance of thermally toughened glasses is exactly the same as that of the same annealed glass.


  • Edge finishing

    The following edge finishings are available for heat-strengthened glasses:

    • Arrissed edges
    • Ground edges but some bright areas permitted
    • Ground edges but – no bright areas
    • Polished edges

    For buildings, the heat-strengthened glass will be supplied as standard with arrissed edges but depending on the requirements of the particular application, a different finish may be possible. Ground polished edges are normally only destined for nonbuilding applications.

  • Other finishing options
    • Holes
    • Notches

Glasses may be heat-treated to enhance their resistance to mechanical and thermal shocks.


Heat Strengthend Glass

Thermally Toughened Glass

Thermally Toughened HST Glass

Tempered glass table