The service life of the tempered glass
Physical tempering is to heat the glass and then cool it rapidly, which changes the structure between molecules inside the glass; chemical tempering is to exchange ions on the molecular structure of the glass surface at high temperature; both methods permanently change the microstructure of the glass material. Therefore, the tempering characteristics will not decay or change under normal use without a high temperature and strong chemical action.
Insulating glass is a combination product consisting of the glass substrate, spacer frame (aluminum strip), desiccant (molecular sieve), and sealing material (butyl glue, polysulfide glue, or structural glue). In the composition of insulating glass, glass, and aluminum frames are usually very stable, and the service life of insulating glass depends on the service life of molecular sieve and sealing material. Due to changes in ambient temperature, the gas in the hollow cavity is always in a state of expansion or compression, so that the insulating glass sealing system is always under stress. At the same time, ultraviolet rays, water, and moisture in the environment will accelerate the aging of the sealing system, thereby causing water vapor to enter the hollow cavity faster. When a large amount of water vapor appears in the hollow glass cavity, the hollow glass has failed. The failure of the hollow glass means the end of the service life of the hollow glass. The key to ensuring that the hollow glass does not fail is the desiccant and the sealing material.
Regarding the life of hollow glass, my country's glass companies first referred to the US standard and gave the concept of a 10-year warranty period; in the national standard for hollow glass GB/T11944-2012, a reference agreement was first proposed for the life of hollow glass, proposing the concept of "the expected life of hollow glass should be greater than 15 years". The life of hollow glass is closely related to the selection of hollow glass materials and processing technology and is also affected by many factors such as the layout composition of the hollow glass and the use environment. It is difficult to quantify it simply. For hollow glass that has been installed on the wall, the simpler measurement method is actually to measure the dew point or the air humidity of the spacer layer.
The life of Low-E glass
The life of Low-E glass mainly depends on the life of the hollow sealing system in which it is located. We know that the main components of the Low-E film layer are metals, alloys, metal oxides, and metal nitrides. Metal nitrides are generally used as protective layers in film structures, and their performance is very stable. Metal oxides and alloy layers are generally used as dielectric layers in the film layer to connect the silver layer and the protective layer, and their properties are also relatively stable. The silver layer in Low-E is relatively active, but its oxidation requires water vapor. Therefore, as long as the insulating glass does not fail, there is no need to consider the life of the Low-E film layer alone.
Life of laminated glass
Laminated glass is a composite glass product in which one or more layers of organic polymer interlayer are sandwiched between two pieces of glass. After process treatment, the glass and the interlayer are permanently bonded together. Even if the laminated glass is broken, the fragments will be stuck to the film, which effectively prevents the occurrence of fragments piercing penetrating, and falling incidents, ensuring personal safety.
The life of laminated glass mainly depends on the material of the interlayer. Normally, wet laminated glass and EVA laminated glass are mainly used for indoor partitions, not for building doors, windows, or curtain walls. Wet laminated glass will age faster under sunlight, and will turn yellow after 1-2 years. After 2-3 years, debonding bubbles, ice, and fogging will appear. Generally speaking, wet laminated glass ages much faster than EVA laminated glass. EVA laminated glass can have a lifespan of more than 10 years if it is used indoors away from direct sunlight.
