Tempered or toughened glass is a type of safety glass processed by controlled thermal or chemical treatments to increase its strength compared with normal glass.Tempering puts the outer surfaces int -o compression and the interior into tension.Such stresses cause the glass, when broken,to crumble in -to small granular chunks instead of splintering into jagged shards as plate glass (a.k.a. annealed glas -s) does.The granular chunks are less likely to cause injury.
As a result of its safety and strength, tempered glass is used in a variety of demanding applications, including passenger vehicle windows, shower doors,architectural glass doors and tables,refrigerator tr -ays, mobile screen protectors,as a component of bulletproof glass, for diving masks,and various type -s of plates and cookware.
The strain pattern resulting from tempering can be observed by viewing through optical polarizer, such as a pair of polarizing sunglasses.
Uses：
Tempered glass is used when strength, thermal resistance,and safety are important considerations. Passenger vehicles,for example,have all three requirements.Since they are stored outdoors,they are su -bject to constant heating and cooling as well as dramatic temperature changes throughout the year. Moreover,they must withstand small impacts from road debris such as stones as well as automobile a
-ccidents. Because large, sharp glass shards would present additional and unacceptable danger to pas -sengers, tempered glass is used so that if broken, the pieces are blunt and mostly harmless.The wind -screen or windshield is instead made of laminated glass, which will not shatter into pieces when brok -en while side windows and the rear windshield are typically tempered glass.
Other typical applications of tempered glass include:
· Balcony doors
· Athletic facilities
· Swimming pools
· Facades
· Shower doors and bathroom areas
· Exhibition areas and displays
· Computer towers or cases
