ABSTRACT

Whilst producing glass, a controlled cooling-down process is used to decrease residual stresses, which may arise during the transformation from liquid to solid material. Subsequently, to raise the mechanical strength and thermal resistance, residual stresses can be induced in the glass by means of a thermal (or chemical) tempering process. Furthermore, also external stresses may be induced by the manipulation of the window, the manner of supporting, wind (possibly dynamic of nature), etc.