Now many office buildings and residential buildings are large areas of glass curtain wall in order to beautiful, but in the absence of external forces, some glass curtain wall will suddenly burst, many people do not understand why? In order to achieve the required strength, glass curtain walls are generally required to be toughened glass. The high hardness and impact resistance of toughened glass curtain walls can be attributed to the fact that after heat treatment by a tempering furnace, the glass in the building curtain wall forms a strong compressive stress on the surface. The presence of this stress, to a certain extent, counteracts the impact capacity from the outside, so it appears that toughened building glass curtain walls have a high strength and hardness, and that the greater the stress, the higher the strength of the toughened glass.

But this is an unbalanced situation, and it always wants to get back to equilibrium if there is a chance -- the bursting and breaking up of the particles is the bursting and breaking up of the toughened glass. Maybe there are external and internal reasons for the toughened glass to break up.

The external causes include overloading, collision with harder objects, improper clearance (clearance is too small) and edge damage, etc. The internal factors include the defects of toughened glass edge processing, sharp corners, holes and holes, etc. . The stress in the stress concentration areas of the toughened glass is too high, the internal stress of the toughened glass is too high, and the presence of nickel sulfide impurities.

The first two elements are caused by process control in the toughened glass process, and the nickel sulfide element is produced in the glass-on-slide process. The fragmentation caused by internal factors is called self-detonation. The toughened glass of self-explosion is not to be avoided completely, it is also without warning, the probability of its generation is usually 3‰ , but our country is relatively high.

The glass may contain nickel sulfide impurities in the form of small crystals that would not normally cause damage to the glass, but because the toughened glass is reheated, the phase state of the nickel sulfide impurities is changed, the high-temperature alpha state of nickel sulfide freezes when the glass freezes, and it may take years for it to return to beta state. Since the low-temperature beta-state nickel sulfide impurities will grow in size, local stress concentrations in the glass will occur, and toughened glass will self-destruct. However, only larger impurities can cause toughened glass, and only when the impurities are at the center of the tensile stress.