Glass is an artificial material that is synthesised using the fusion process. It is brittle and transparent in nature. Although both the transparency and the brittleness can be altered if the individual components used to manufacture glass are altered. The primary components used in the manufacturing of glass are sand which is fused with soda and lime along with a few other components and cooled rapidly.
Glass materials are of various types but this post will shed some light on the primary variations of glass that are popular in the engineering sector.
Engineering glass types:
Glass manufacturers, in order to meet the requirements of the engineering sector, offer various types of glass materials. That being said, engineering glass materials are mainly subdivided into three distinct categories. They are as follows:
Hard Glass
These are silica-based glass materials that have a CTE (or Coefficient of Thermal Expansion) of less than 6 ppm/°C. This type of glass is mainly used with sealing agents like tungsten, Kovar and molybdenum for enhanced results. Examples of hard glass are – Alkali Borosilicate, Alkali Barium Borosilicate, etc.
Soft Glass
Glass materials with CTE value higher than 6 ppm/°C are called soft glass. It is mainly used as a hermetic seal between stainless steel housings and alloy fixtures. It is also used as the primary component when one is looking for proper compression sealing. Alkali Barium Glass and Soda Lime Glass are some examples of Soft Glass.
Speciality Glass
Glass materials that are used in special conditions like sealing a lithium battery unit or ceramic-glass composites are called speciality glass. This category of glass finds extensive applications in sectors ranging from aviation to dentistry.
Special engineering properties of glass that matters:
Glass is one of the most extensively used raw materials in the manufacturing, engineering and construction sector. Glass has several engineering properties that make it an excellent artificially created raw material. Some of those engineering properties are as follows:
- Glass Transparency – is the most important factor that makes a glass material ideal for use in various industrial as well as engineering applications. In case one is planning to use glass materials in a construction project or on the reflective panels of satellites, they should be going for glass materials that are high on the transparency factor.
- Overall Strength Of Glass – depends on the rupture value of glass. Although glass is a brittle material, the strength of the material can be enhanced by many folds by adding strength enhancing additives. This is the reason why glass materials used in aviation and space engineering differs from the ones used in other sectors.
- The Transmittance Factor Of Glass – is the amount of light that can pass through a unit area of glass at any given point in time. The glass used in the window panes of aircraft and automobiles has high transmittance factor.
- U Value Of Glass – It is a technical term that simply states the amount of heat that can be transferred through a unit area of the glass at any given point in time. If one is looking for glass materials that can be used as an insulator, they should be investing in glass materials that have low U-Value.
- The Ease Of Recycling Glass – Glass, be it in any form is recyclable but the maximum number to which a particular block or sheet of glass can be recycled differs based on its composition.
As you can see in the above sections, glass has several properties that make it a fine material for use in both technological as well as the engineering sector. Other properties that further strengthen its position in the commercial sector are its ability to withstand corrosion caused by acids, solvents and bases.