At a time when humanity has learnedreceive metals from ore and process them, a new round of technical progress has begun, which continues to this day. If before the appearance of plastic in the distant 1835 the main strong materials that were available to people were metals and wood, now plastics have been added to the list. Nevertheless, it is impossible to imagine an area where metals and their alloys would not be used. It can be said that progress in its existing form became possible precisely because of them.
It is understandable that physical and chemicalthe properties of metals have been very well studied. Now everyone is familiar with the basic ones. In this paper, we will consider in detail the general physical properties of metals. However, in order not to confuse the two terms, we will give a short list of what exactly is meant by chemical properties.
First of all, this is the ability of metals to joinin interaction with gases, water and other substances. Solubility can also be classified here. All this determines the oxidizability, corrosion resistance, etc.
Physical properties of metals are presentedelectrical conductivity, density, magnetic permeability, heat capacity, as well as coloring, ductility, etc. The full list is quite large, so here it is not given. We list only the basic physical properties of metals.
Imagine a situation: winter, cold.On the street there are two benches - wooden and metal. Which one is more cold? Even a child knows that metal. However, the air temperature is the same, therefore, the concept of "cold" in this case is not applicable. What causes a cold sensation? Physical properties of metals. In particular, the thermal conductivity and heat capacity. Due to the peculiarities of the structure of the atomic crystal lattice, metals consume thermal energy much more quickly, while evenly warming up. This feature makes it easy to make connections by welding or soldering.
It is known that for the smelting of certain metals,high temperatures, while others can be melted literally in the hands. For example, a sodium metal passes into a liquid form already at 100 degrees (a little less), so anyone can feel like a metallurgist. Its opposite is tungsten (from which filaments are made in lamps), which melts at 3400 degrees.
Of course, the physical properties of metals do notare exhausted. Imagine that it is necessary to make and install a metal door. Accurate adjustment of dimensions without "reserve" will lead to the fact that in the hot season, due to the linear temperature expansion, the door can not be closed (or opened). Accordingly, with a decrease in temperature, the dimensions of the product slightly decrease by a factor F. All these points must be taken into account.
Huge importance metals have forelectrical engineering. Of these, almost everything is done: from the conductors to the hulls of electrical equipment. Copper and aluminum are used for the production of wires, since they have the least resistance to the passage of charged particles. It is worth noting that the best characteristics of gold and silver, but because of the high cost of these metals, they are used in a limited way. The interconnected property is the electrical resistance. From these materials, heating spirals, filaments, etc. are made. Representatives of this group of metals are tungsten and nichrome (alloy).
One of the most important elements of electric circuits isinductor. It is enough to make a core of soft magnetic material into it, as the operating mode changes radically. This is due to the magnetization of the metal.
The required characteristics of the product can be obtained only if you know the physical properties of the metal used.
