How are diamonds processed?

Diamond is a natural mineral that is carbon with an allotropic crystal lattice. Due to its molecular structure, it is an extremely hard material that can be stored indefinitely.

The chemical composition of a diamond can be altered by various factors: high temperature, pressure and / or vacuum. As a result of their action, the diamond turns into another chemical element - graphite, which has a different composition of qualitative characteristics.

Diamonds are obtained by natural mining and artificial production. In the second method, the chemical element graphite is exposed to high temperature and pressure. The graphite material changes its molecular structure and turns into rough diamonds, acquiring characteristic strength properties.

The history of diamond mining is extremely young. This is due to the complexity of the search and extraction of the mineral, as well as the difficulties associated with its processing. The technology of processing the described material with the help of another diamond began to gain popularity only by the XIV-XV centuries AD. Until that time, this method was used only by ancient Indian masters, who carefully kept the secrets of technology.

On the territory of Russia, the development of mineral deposits and the development of technologies for its processing took on an industrial scale only in the second half of the 19th century.Today in Siberia, work is underway to extract this mineral at mines that are in the list of the largest in the world. At the same time, all types of diamond processing have been mastered.

The processing technology and the set of technical devices suitable for this are determined by the name of the final purpose for which the cut diamond will be used.

The characteristics of diamond necessitate its use in various technological systems, tools and devices. For example, a fine diamond fraction - grit, is used as a sputtering coating on the working surfaces of any cutting devices. Diamond spraying is used for application on cutting discs, saws, bands designed for sawing metal, stone, concrete, ceramics and other materials.

Despite the resistance of diamond to the effects of destructive loads of a wide range, it is a fragile material... The use of impact-pressing technology makes it possible to grind diamonds into chips. The crushing of the mineral is carried out using a hydraulic press (this processing option is rarely applicable).

The technology of rolling milling is more widely used. As part of this process, the raw material is fed through a conveyor into a special chamber, in which cylindrical rollers in contact with each other rotate. Passing between them, rough diamonds crumble. Considering the strength factor of the diamond, the conveyor uses several blocks with rotating rollers that have different sizes of the gap between them. This makes it possible to reduce the load on the mechanism, since stage-by-stage crushing is carried out according to the principle from larger to smaller.

The size parameters of the crumb fraction are determined by the name of the final purpose for which it will be used. Coarse diamond grit is used for rough processing of materials with an increased strength factor: ceramics, granite, porcelain stoneware. For example, coarse chips are used as a cutting element applied to the working edge of circular crowns designed for cutting round holes in hard materials: ceramic tiles, concrete, granite slabs and others.

Diamond grit of finer grain size is used for fine processing of certain materials. As part of this processing, materials are smoothed, polished, polished. Polishing is done with a special paste based on diamond dust. Diamond grit of different grain size is obtained by crushing and subsequent sieving.

The process of obtaining diamond materials suitable for industrial applications is a more laborious procedure than impact-pressing technology. These materials include, for example, glass cutting wheels, turning tool tips and others. They are elements made entirely of diamond mass. The production of such additions involves carrying out production procedures associated with resource costs and the use of several processing technologies at the same time.

The strength properties of diamond make it much more difficult to manufacture parts that place high demands on dimensional parameters and shape accuracy.

The right combination of factors affecting the machining tool and the material to be cut allows for the most efficient machining. For example, in some cases, the workpiece to be processed is heated within a mid-temperature range, and the temperature of the processing tool is kept in the low thermal range. In this case, the heated workpiece can be machined, and the percentage of tool wear is reduced.

Another way of working with a diamond is with hot iron. This mineral is capable of entering into a chemical reaction with a metal heated to high temperatures. Hot iron begins to absorb the carbon component of the diamond. At the point of contact of a hot metal with a mineral, the latter melts at the molecular level.

This method has low production efficiency, however, only with its help it is possible to achieve certain results in the processing of diamond material.

The hot steel method is used when it is necessary to cut a large volume of raw materials with a minimum waste ratio. This method uses glowing steel wire driven by rotating shafts. In this case, the cutting line is as thin as possible, and the loss of the main raw material is minimized.

With the hot sawing method, only general processing manipulations can be performed. Detailed cutting is carried out using more sophisticated grinding technologies. Hot drilling technology is also used within this method. In this case, the drilling steel element is also heated to high temperatures. The effectiveness of the method also increases due to heating of both parts as a result of friction against each other.

Diamond drilling is used to perform roughing operations. Holes of the required diameter are drilled along the split line of the workpiece. Special anchor expanders are immersed in them. The technology makes it possible to control the expansion of the anchors one by one or simultaneously. Thanks to this, it becomes possible to perform controlled splitting of the workpiece along a given line.

The main direction in the processing technologies of this mineral is its grinding. Thanks to this procedure, diamonds take their final shape, and in some cases turn into precious stones.

When making diamonds, craftsmen use step-by-step processing methods. The rough workpiece is cleaned of impurities of other minerals, if any. Then a rough sawing is performed, due to which the main shape of the future product is formed. After that, cutting begins.

For grinding a diamond mineral, devices are used, equipped with special attachments - discs or plates having a thickness, shape and material of manufacture corresponding to the name of the procedure being performed. The working surfaces of these attachments are coated with fractions of diamond chips of various diameters.

If the cutting is done with the aim of obtaining a precious stone - a diamond, then a variety of tips with a wide range of dimensional parameters are used. The first to be used are plates or discs with diamond grit of the largest diameter. As the process proceeds, the granularity of the nozzles decreases. The final polishing is carried out using diamond nanoparticles.

The tools with which the cutting is carried out differ in their intended purpose and principle of operation. Some of them function due to the presence of the rotary motion of the rotor, on the end shaft of which a grinding disc is attached. Other tools work on the principle of reciprocating motion. Grinding plates are inserted into the special clamps of these tools.

In the process of processing, diamonds are ground to a transparent glassy state. Due to the fact that the facets of the future diamond are located in strictly verified positions and at a given angle, the rough raw material is transformed into a precious stone. At the last stage of processing, it is polished to a mirror-like state.

You can find interesting information about diamond mining and processing in the next video.