What Kind of Glass Is Used in Oven Doors?

The glass used in oven doors must withstand high heat while simultaneously keeping the temperature inside the oven at a steady temperature and providing a clear view inside. Not all glass is right for the job. Tempered glass has the desirable characteristics thanks to its durability, safety and low conduction.

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What Kind of Glass Is Used in Oven Doors?

How Tempered Glass Is Made

Glass is first prepared for tempering. It is cut into desired size and sandpaper is used to remove sharp edges off the glass. The glass is then washed and sent into a tempering oven, which heats the glass to 620 degree Celsius. Then the glass goes through quenching, a high-pressure cooling procedure. High-pressure air is blasted on the glass, which makes the surfaces cooler than the inside. As a result of this, the outer surfaces go into compression and the inner part remains in tension.

What Is Tempered Glass?

Tempered glass is also known as safety glass, and because it is hard, it is also used in the windshields of cars. Tempered glass is usually preferred in situations where ordinary glass can easily break. Tempered glass is five times stronger than normal glass. Another great advantage of this kind of glass is that if it breaks, the glass does not form sharp shards. Instead the shards are small and round, much like pebbles.

Strength of Tempered Glass

Tempered glass is five times stronger since the manufacturing process of this glass is completely different from regular glass. Early on in its manufacturing process, the tempered glass is subjected to extreme heat and pressure, after which is it made to cool off rapidly. This sudden change in temperatures causes the glass to become more stable and strong.

Uses of Tempered Glass

Tempered glass is most likely to only crack in situations where the normal glass would shatter. Therefore, it is used in places where there is high pressure or heat. For instance, computer screens are made of tempered glass so that they are safer. Glass shower stalls, oven doors and coffeepots in percolators are also made of tempered glass.

How Tempered Glass Breaks

The curing of tempered glass makes it brittle in such a manner that the entire panel shatters at once, instead of shattering on a localized point of impact. Since tempered glass is also very strong, it may not break immediately, but only crack. However, if there is a crack in the tempered glass panel, it will eventually break if there is continuous stress on the glass.


Alo holds a bachelor's degree in journalism and technology from the University of Washington in Seattle. Working as an advertising director with a marketing firm. Also a freelance writer focusing on the areas of electronics, media, culture, business, personal finance, home improvement, leisure, and technology.