Being one of the most ancient materials, glass has been used by mankind for more than one thousand years. The versatility of this substance has allowed him to find application in a wide variety of industries. By its physical and chemical properties, glass belongs to inorganic compounds, it is solid, has an amorphous structure, and isotropic.
For each type of glass, the transformation of the state of aggregation from a fluid, extremely viscous to a glassy type is characteristic during the manufacturing process. The production technology provides for its cooling at a speed that does not allow to go into the crystallization phase of the melt.
The melting point of glass depends on its quality and expected characteristics. Typically, cooking takes place over a fairly wide temperature range from 300 to 2500 ° C. The properties of this substance depend on the components that make up the glass-forming melts. Their list is quite extensive and is represented by various oxides, phosphates, fluorides and other additives. At the same time, classical transparency is by no means the last characteristic for various types of glasses found both in nature and synthesized during production.
The most ancient glass crafts dating back to seven centuries BC were discovered by archaeologists excavating in Egypt. These were beads and amulets. But several millennia passed before the first industrial enterprises, glassworks of the eighteenth century, appeared. A feature of glass production in the charges was that the melting temperature of the glass was achieved using coal, and boilers for cooking became closed.
Prior to this, firewood was used as fuel, glassmaking workshops were not in place for a long time, stoves scattered, and fuel in the district was quickly consumed. The boilers were open, firewood did not emit substances that affect the transparency and color of the output product. The melting temperature of glass in a technological process of this type reached 1450 ° C.
An important event was the invention at the beginning of the 20th century of a method for producing sheet glass, named after its developer Emil Furko, who proposed a machine-based method of drawing. Existing until 1959, it was supplanted by the Float method developed by Pilkington.
The main components of ordinary glass are quartz sand in a proportion of 69-74%, soda (12-16%), dolomite and limestone (5-12%). But in the technological process of production, it is important not only at what temperature the glass melts, but also what is the cooling rate of the melt. Theoretically, with rapid cooling, it is possible to obtain a vitreous from a metal, the main thing is to have time to cool the melt until a crystal lattice is formed.
With all the variety of attractive properties of ordinary glass, there was an urgent need for a more durable and lightweight transparent material. First of all, it concerned the industry specializing in aircraft manufacturing. Plexiglas got its name only by its external resemblances to traditional glass.
Its impact resistance is five times higher, it is 2.5 times lighter. By light transmission, it reaches a level of 92%, has a high resistance to aging. Plexiglass is much easier and more affordable to handle. The melting point of plexiglass is in the range of 90-105 degrees, which allows it to be subjected to heat treatment.
But both of these materials each occupied their own niche in modern production. Traditional inorganic glass firmly holds its position and is not going to take them to the latest organic polymers.
The use of a wide range of various impurities and additives makes it possible to obtain not only the amazing optical characteristics of glass, but also significantly improve its mechanical properties.
In addition to industrial use, it is impossible not to note the role of art glass. Glass-blowing masters, continuing the traditions of ancient artists, turned the creation of masterpieces from glass into true art. In the furnaces of their workshops, the melting temperature of glass is reached, working almost by hand, in their work they not only show an extraordinary imagination, but also spend a lot of physical effort.