• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Where is toughened glass used?

Extracts from this document...


Storyboard Where is toughened glass used? Toughened glass can have various uses, mainly for when all the properties of normal glass are required, but also the stronger properties that toughened glass has. It is used in situations that glass would just not be strong enough for, such as in frameless shower screens or office partitions inside buildings, or on the exterior of buildings where large spans of glass are required, such as office buildings where the exterior is mainly glass. It is also used a great deal in all forms of transport for windows and windscreens, as regular glass could not stand up to the conditions that many vehicles face. The main use of toughened glass being focussed focused on today is in car windscreens. Toughened glass must be used for these, and in most countries there are regulations in place regarding the thickness and strength to ensure that safety is always at a high standard. It is necessary to use toughened glass in this situation due to the fact that regular glass could prove very dangerous to the occupants of the car if it were to break. ...read more.


is carried out before the toughening process starts. Otherwise, if these are attempted on the treated glass, it will just shatter due to the incredibly high tension and compression within the glass. This extra stage is a heat treatment process which, when performed correctly, should make the surface be in compression while the centre is in tension. Basically, the glass is heated to a very high temperature (approx. 620?C) until it begins to soften. It is then cooled very rapidly using cold jets of water or air. This brings the temperature of the surface of the glass down to room temperature quickly, so quickly that the centre of the glass is still very hot. This means that the surface molecules settle as they are, as they do not have time to move around from being heated to cooled. However, the particles in the center of the glass cool down much more slowly, meaning that they move closer together causing the center of the glass to shrink while the surface is already solid, therefore cannot shrink. This causes the surface of the glass to be forced into compression and the center is put into tension. ...read more.


Other properties The way that toughened glass breaks is not the only difference from normal glass. Some of its other properties are also different. For example, the toughening process involved in making toughened glass can slightly reduce the optical quality. Slight distortion of the surface can be seen when light reflects off the glass at certain angles, but not greatly enough to affect the vision of drivers when it is used in car windscreens. The resistance of the surface of the toughened glass to scratches is not changed by the heating and cooling from that of regular glass. Generally, toughened glass is never any thinner than 6mm with a density of about 2.5kg/m squared. It also has a high compressive strength value of 1000Mpa. This means that 10 tonnes would be required to shatter 1cm cubed of toughened glass. The Young's Modulus of toughened glass is about 70Gpa (Giga Pascals). It can withstand temperatures up to 295?C. All of these properties make it the most suitable choice for car windscreens, as it can withstand much more stress and pressure, and is a stronger and safer option that normal glass. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Resistant Materials section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Resistant Materials essays

  1. What factors affect the cooling of hot water in a container?

    Overall changing the insulating material of an object has proven to have quite an impact on its temperature. Evaluation: Fortunately we didn't encounter any major problems whilst conducting this experiment. Just minor ones such as it was quite hard wrapping the foam around the beaker, but we managed to overcome it with some extra Sellotape.

  2. The Evidential Value of Glass Fragments.

    To express the refractive index as an equation we look at the following diagram: From the diagram we see that 1 is the angle of incidence (? i) while 2 is the angle of refraction (? r) and by using Snell's Law we can equate the refractive index to be: RI = (sin?

  1. The task has been set to make a hole punch (used to punch holes ...

    This is achieved by altering the punch shape. Bolt-Together Modelling Kits: Meccano Meccano is one of the many popular 'bolt together' modelling kits that are available on the market today. Long strips of metal are bolted together with other such components to produce larger models - like the one on the right.


    gravity Solubility in 4.2 molar HCL Solubility in 90% (C*) (F*) Room temp. Boiling formic acid 66 250-260 482-500 1.13-1.16 Insoluble Soluble Soluble Modified 66 250-260 482-500 1.08-1.10 Insoluble Partly Soluble Partly Soluble 6(Monomer extracted) 210-225 410-436 1.12-1.14 Soluble Soluble Soluble 6(Monomer not extracted)

  1. My aim of this experiment is to recognize which material is the greatest sound ...

    was in the property of the material as there are more molecules per unit then this will absorb the sound more and be a better insulator of sound. If there are fewer molecules in one material then the sound will easily be able to travel because it does not loose

  2. A new branch of a major Chinese take away, Wok In, is opening in ...

    Better handles offer a larger contact with the hand and where the force can be spread out evenly over a larger area. Texture can help improve grip and avoid slipping. In my research I gathered information, which will help me design and make packaging for a range of fast food products.

  1. Investigation into the physical properties of glass.

    This cools the surface but leaves the middle hot. When the middle cools it contracts, the surface contracts with it, meaning that the surface has contracted twice and is now under compression. To break the glass this compression must first be overcome.

  2. Aristotle and Cause.

    He also raised the question if there could be a form but no matter and he concluded that this is God. What causes something to be what it is to have the characteristics that it has, or to change in the way that it does?

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work