What makes some glass fire resistant?

  1. shazwellyn profile image56
    shazwellynposted 5 years ago

    What makes some glass fire resistant?

    Fire and heat helps to make glass into glass.  But why doesn't some glass melt back into a molten state when heat and fire are applied?  Examples of glass that is fire resistant:  Woodburner stoves and pyrex dishes.

  2. Randy M. profile image86
    Randy M.posted 5 years ago

    They add boric acid to the melted slica to make borosilicate, or heat-resistant, glass.

  3. ackman1465 profile image62
    ackman1465posted 5 years ago

    Further to Randy's:   Borosilicate glass is not particularly "heat resistant"... insofar as its melting temperature is about the same as "regular" silicate glass (like window panes).....     

    The property that makes borosilicate  "heat resistant" is that it's coefficient of expansion is far lower than "regular" glass... hence it is not so likely to fracture (shatter) when it experiences temperature differences.....  That's why "Pyrex" cookwear can be used on a stove or in an oven.... and it is used in fireplace doors....