Each of us more than once met glass. What is this fragile and transparent material, any student knows. Every day we see him in mirrors, windows, in dishes and furniture elements, but are we well acquainted with him? How is it made, what is it and what are the properties of glass?
What does this word mean
There are many reference materials that can help in this matter. What is the meaning of the word "glass" according to one of the most popular sources? Ozhegov’s Dictionary describes this substance as a solid material obtained from quartz sand mixed with oxides of certain metals. Even the definition gives some idea of the method of production of this material. But we will move on to this topic later.
Surely everyone is used to the fact that glass is a transparent material. But pay attention - Ozhegov’s dictionary does not provide such a clarification. Glass can be not only transparent, but also colored or frosted. But the composition of the material does not differ significantly.
What glass is made of
The standard composition of the glass is a mixture of pure quartz sand, lime and soda. Various additives can be used to change material properties. But nevertheless, the main component is pure river sand. Its amount is approximately 75% of the total mixture. Soda can reduce the melting temperature of sand by almost 2 times. Lime protects glass from exposure to most chemicals and also adds strength and sheen.
Additional impurities:
- Manganese. It is added to the glass to produce a specific green tint. For other colors, nickel or chrome can be used.
- Lead gives the glass extra shine and a distinctive ring. The material is colder to the touch. Glass with an admixture of lead is called crystal.
- Boric acid oxide also gives the material additional gloss and transparency, while lowering the coefficient of thermal expansion of products.
History of glass production
Even 6000 years ago, people were able to create this beautiful and fragile material. Of course, its appearance was somewhat different from modern glass, since in Ancient Egypt and Mesopotamia there was no equipment for high-quality cleaning of sand and other tools. Nevertheless, glass production began there. Due to its resistance to environmental influences, this material gave historians an idea of the culture and technical capabilities of ancient peoples.
In Russia, the first glass factory appeared in 1636. It was located near Moscow. There were created dishes and
windowpanes. This industry was greatly developed under Peter I.
Only in 1859 the invention of the high-pressure pump allowed the creation of glass without the participation of glass blowers. This greatly simplified production. And at the beginning of the 19th century, an interesting property of the material was discovered - if the finished product is heated to a certain temperature, the mechanical properties of the glass will increase by 400%.
Modern production
Technology has stepped far forward, which allowed the creation of any materials in huge quantities and with the lowest human cost. Currently, there are many factories in which glass is created using standard established technology. What is modern material obtained from molten quartzite sand, we learn by familiarizing ourselves with the technology. Take sheet material as an example.
Glass production by stages:
- All the necessary ingredients are loaded into the oven and heated until a liquid homogeneous mass is formed.
- In a special homogenizer, this alloy is mixed until smooth.
- The resulting mass is poured into a flat container, at the bottom of which is molten tin. There, the glass is distributed, forming a uniform thin layer.
- The cooled and hardened material is sent to the conveyor. There, control of the thickness of the glass and cutting is carried out. Material that has not passed inspection, as well as defective parts, are sent for re-melting.
- The last quality check is carried out, after which the glass enters the finished goods warehouse.
Types of glass
Currently, this material is one of the most common. It is not surprising that there are various types of glass that differ both in appearance and in physical properties. Here are some of them:
- Crystal glass. This is a material containing lead in its composition. We talked about him above.
- Quartz glass. It contains pure sand, which is why it is highly durable. It is able to withstand temperature jumps, therefore it is used to create optical instruments, laboratory glassware and windows.
- Foam glass. Lightweight building material that can be used both for decoration and for laying walls and floors. It contains a large number of voids, due to which it has high heat and sound insulation properties.
- Glass wool. Volumetric air material consisting of thin and very strong threads. Fire resistant, therefore, is used not only in construction, but also when sewing firefighters and welders.
Glass application
Almost any application can be found for this material depending on the properties and appearance. The main consumer of glass made in our time is the construction industry. It uses more than half of the manufactured material. Its purpose can be very diverse - wall cladding, glazing, erection of walls made of hollow bricks, thermal insulation, etc. Stained glass can also be attributed to the construction industry . What is a gothic window, everyone knows for sure. As a rule, it is laid out from a large number of colored glass. In our time, stained-glass windows have not lost their relevance and are used both in construction and in the manufacture of furniture.
In second place in popularity are glass vessels for various purposes. A little less tableware is made. It is worth noting that in the chemical industry glass is an indispensable material, since it is resistant to most reagents.
Physical properties
Like any other material, glass has a number of qualities that you need to know before using it in a particular area.
- Density. It may vary depending on the composition of the mixture and the manufacturing method. The value of the density of the glass can vary from 220 to 650 kg / m 3 .
- Fragility. This characteristic is a distinctive feature of glass and limits its use in the construction field. Currently, scientists are creating more complex alloys that maximize the strength of the material.
- Heat resistance. Regular glass can withstand temperatures up to 90 ° C. After processing, the thermal properties of the material are significantly increased. For example, industrial glass is able to withstand temperatures above 200 ° C.
Interesting Facts
We learned a lot about glass - what it is, how it is made, and what properties it has. It's time to take a break and get acquainted with the most interesting facts about this very common material. Few people know that:
- The speed of the crack along the broken glass is 4828 km / h.
- The decomposition time of this material is approximately one million years.
- Glass can be repeatedly melted with virtually no loss of quality. In this regard, it has almost no analogues.
- Being an amorphous material, molten glass does not harden with rapid cooling. This requires special conditions.
Glass is not in vain so actively used in construction and other areas of human life. Surely it will remain one of the most popular materials for a long time. This statement is supported by the strength, durability and relative simplicity of glass manufacturing, due to the fact that the components for its creation are present on Earth in large quantities.