What are the causes of self-explosion of tempered glass?

2019-10-18 10:03:38

Can tempered glass explode spontaneously? Perhaps many people will feel strange, what is tempered glass self-explosion? Self-explosion of tempered glass refers to the phenomenon of automatic explosion of tempered glass without direct mechanical external force. What are the causes of self-explosion of tempered glass? There are many reasons for self-detonation, which can be summarized as follows:

 

1. There are stones, impurities and bubbles in glass: impurities in glass are the weak point of tempered glass and also the stress concentration point. Especially if the stone is located in the tensile stress zone of tempered glass, it is an important factor leading to the explosion.

 

2. Glass contains nickel sulphide crystals. The self-explosion of tempered glass is caused by the change of phase transformation volume of nickel sulphide crystals.

 

3. Defects such as scratches, blasting openings and deep explosion edges are easily caused by improper processing or operation of glass surface, which may lead to stress concentration or self-explosion of tempered glass.

 

4. The uneven stress distribution, offset or excessive stress in toughened glass. Generally speaking, the causes and conditions of self-explosion in glass tempering process

 

Most of them are 3 and 4, most of them are self-explosion after glass leaving factory in case 1 and 2, and most of them are case 1 after glass installation is completed. How to identify the self-explosion of tempered glass? The difference between tempered self-explosion and impact fracture of tempered glass is mainly due to the difference of "initiation point". Generally, the initiation point of tempered glass self-explosion is in the center of the glass. At the center of the initiation point, there is a clear butterfly-like fragment, commonly known as "butterfly spot".

 

External impact breakage of tempered glass can be seen at the breaking point without butterfly spots. Fragmentation of glass is radioactive from the impact point.