Tempered glass in the absence of direct mechanical force under the automatic burst is called tempered glass explosion, according to industry experience, ordinary tempered glass of the rate of 1~3‰ around. Self-detonation is one of the inherent characteristics of tempered glass.
There are many reasons for the expansion of the self explosion, and simply generalize the following:
Effect of ① glass quality defects
A, the glass has stones, impurities, bubbles: The glass impurities are the weak point of tempered glass, but also stress concentration. Especially if the stone is in the tensile stress zone of tempered glass, it is an important factor to cause burst.
The stone exists in the glass and has different expansion coefficients with the vitreous. The stress concentration in the surrounding crack area of the stone is increased exponentially. When the swelling coefficient of stone is less than that of glass, the tangential stress around the stone is in the tensile state. The crack propagation in the presence of stones is very easy to occur.
B, glass containing nickel sulfide crystal
Nickel sulfide inclusions are generally present in crystalline spheres, with diameters of 0.1-2 ㎜. The appearance is metallic, and these inclusions are ni3s2, NI7S6 and Ni-xs, of which x=0-0. $number。 Only the NI1-XS phase is the main cause of the spontaneous crushing of tempered glass.