The concept of "dislocation" is used in various fields of activity. It can be found in science, military affairs, jurisprudence. For example, when distributing justices of the peace they talk about their deployment. This concept came from Latin words, and in translation means "dislocation", "move", "displace", "place", "put".
Chemistry
Consider the concept of crystals. These structures may have some defects. They look like lines, and the atomic particles themselves are not placed correctly. It is such a change that is called dislocation in crystals. They become structurally sensitive, some of their properties change. Dislocations are violations both externally and internally. The crystal itself loses its mechanical properties, it becomes not so strong and elastic.
Classification
The dislocation is edge and screw. If the crystal is perfect, then along its entire length the atomic planes are placed in parallel. But when they are torn inside the structure itself, this leads to an edge dislocation. This means that an extra half-plane is formed. It is called the axis of deformation. If you use a microscope, you can observe this picture in detail and see how specifically atomic rows are located. If the crystal itself is cut into four parts along the plane, then the lowermost layer is shifted 1 interatomic distance relative to the upper one in the perpendicular direction, and after that all the atoms are again fastened at the edges opposite to each other, then such a picture will perfectly illustrate the edge dislocation. The second notch is the direction of the shift, which is called the Burgers vector. The slip plane of this dislocation will pass through it and the defect line itself. Thus, this extra plane was formed. The crystal itself has already lost its appearance and does not look at all as it should.
Dislocations are a kind of stress. They occur within the structure. Before the shear itself, all parts of the crystal are strained together, highly elastic. But then this condition weakens. In this case, changes begin inside the source, which leads to dislocation. Shear vectors that are in tension due to
polarized light can both attract and repel. If these vectors are the same, then a shift is observed in the crystal, namely, the structure is stretched to one side and glides to the other. As the dislocation approaches, this shift is compensated.
Moving
The crystal may be deformed, but this happens for a reason. At this moment, dislocations simply move inside. This phenomenon is better known as gliding. When this process occurs, the crystal is deformed by a distance equal to the second notch. But in this case, deformations are noted not between all atoms, but only between those that are on the axis. And this means that the intervention of external factors is not required. Everything happens with relatively low stresses, especially when compared with processes in ideal crystals that change without dislocation. This can be observed by the example of threadlike structures.
General properties
Both dislocations can slip perpendicular to the surface, which leads to crawling. This phenomenon is due to the fact that there is a diffusion of atoms, but when the temperature decreases, mutual penetration slows down. If there is a strong load, then all the atoms seem to resist this and crawl to the position they need. In this case, the slip does not occur. And ongoing processes are aimed at reducing stress. The deformation itself is directly proportional to the dislocation velocity. And in general, if changes without a shift are possible, then only when diffusion takes place.
Mobility
Many factors interfere with free sliding. These include, in particular, the strength of atomic compounds, the poor conductivity of electrons, for example in metals, elasticity, interaction with other dislocations, etc. In other words, the fewer these obstacles, the faster the shift becomes. And as soon as the tension rises, so does the slip increase. In general, mathematicians proved that dislocations are topological defects. They are stably formed in crystals. And if two shifts collide, then they will kill each other, disappear. A single dislocation will disappear only when it goes beyond the edge of the structure. Next, we consider other areas of application of this concept.
Armed forces
At first glance, an incomprehensible combination of words, but in fact, everything is quite simple. The deployment of troops is just the alignment of the armed forces, military personnel, units, ships, naval bases. It can occur both on the territory of the country to which they belong, and beyond its borders. A place of deployment is a site of troop deployment before an important battle. At the same time, the commanding staff explains where to send whom, where to relocate for military operations. Any changes to the placement require strict permission. Only companies, battalions and batteries can be moved at the request of the regiments, commanders in which they are located, and the division head can dispose of the battalion, but it is forbidden to leave a certain area. There are special dislocation maps. They include conventional signs of the distribution of forces.
Ships
But the maps on which the deployment of the vessels is indicated carry an information function. In other words, they cannot be used to determine the correct course in sea navigation. A special identification system is used for mapping. The compiled circuit shows where and where the movement of the ships takes place.
Railway transport
On the territory of Ukraine, Russia, Belarus, Kazakhstan, the Baltic countries and the CIS countries, regular wagons are located. And once or twice a day is informed about the placement of trains. These processes occur directly on schedule. You can track movement and distribution manually. There are also automatic methods. They suggest special options. One of them is called "Request to the station."
Road sign location scheme
This entire placement system should include several factors. So, it is mandatory to have a road plan for cars, graphs of curves and longitudinal slopes. In addition, there should be markings on the roads, the layout of signs and restrictions, navigation and the position of traffic lights, junctions (both ground and underground). Mandatory marking of light, public transport stops. There are many applications thanks to which it is possible to determine the location of traffic signs at one or another location. They resemble a map or navigation.
Other cases
In nature, there is even a brain dislocation. This phenomenon occurs when some structures shift relative to others. This process leads to various diseases, in particular to circulatory disturbance, etc. Since the brain does not completely fill the cranium, it can be displaced under the influence of certain factors, thereby deforming. Subsequently, in the absence of timely treatment, the organ ceases to function properly.
Conclusion
So, dislocation is a multifaceted concept. It is used in many fields. This can apply to crystals, to traffic, to military equipment, and even to the brain. In each area, the term acquires an additional meaning, a narrower meaning in accordance with the area under consideration.