Meaning of Metal
What is Metal:
Metal is the chemical element that has the ability to conduct heat and electricity.
Metal is extracted from rocks and is found in nature in a solid state at room temperature, with the exception of mercury, which is in a liquid state. Likewise, metal is characterized by having a high density and a high reflection of light, which in turn gives it shine.
However, when metals are in contact with oxygen or some types of acids, they oxidize and corrode, since they have a low incidence of ions.
Within the definition of metal are included the pure elements such as gold, silver and copper, and metallic alloys such as bronze and steel, which are derived from the mixture of two or more metals or from the mixture of a metal with another non-metal element, for example, carbon.
Metals are among the elements that are widely used by humans. Metals have been used in their natural state since ancient times to make basic tools.
Then, as technological development has advanced, metals have been used in various ways, hence, today they are one of the most important elements in industrial production, especially for their resistance.
Therefore, metals are used for the manufacture of vehicles, kitchen items, construction, electrical cables, among others.
There are different types of metals, among which the following can be mentioned:
Precious metals can be found in the free state in nature and are not alloyed with other metals. They are characterized by having a high economic value and being widely used for the production of jewelry and goldsmith pieces.
For example, gold, silver and platinum, which can be easily identified in various pieces of jewelry.
See also What is gold.
Ferrous metals are those whose base or main element is iron. They are characterized by being heavy, easily corroded, gray in color and have magnetic properties. However, these metals are among the most used today.
Examples include iron, steel, magnesium, titanium, cobalt, and other castings. Many of these metals are used for the construction of bridges, beams, bodies, locks, tools, connecting pieces, among others.
The basic or non-ferrous metals are those that do not have iron as a base element. They are soft metals and have little mechanical resistance. These metals can be differentiated by being heavy (tin or copper) or light (aluminum or titanium).
Aluminum is one of the most widely used non-ferrous metals, it has good resistance to corrosion, is electrically conductive and has a high strength-to-weight ratio.
For example, the most important non-ferrous metals are copper, tin, zinc, lead, aluminum, nickel, manganese and aluminum, among others. These metals are used to manufacture automobiles, airplanes, electrical cables, pipes, motor coils, among others.
Radioactive metals are those that are found in small quantities on the Earth's crust and are extracted through various human activities such as mining, in the extraction of gas or oil.
As an example, plutonium, uranium, thorium can be mentioned. They can be used in the areas of mining, medicine or agriculture, as well as for war.
Properties of metals
The most remarkable properties of metals are:
- Malleability: ability of metals to spread into sheets or plates when going through a compression process.
- Ductility: property of certain metals that allows them to be molded and extended in the form of threads or wires.
- Tenacity: it is the ability of metals to withstand blows without breaking.
- Mechanical resistance: ability of metals to resist torsion, bending, traction or compression without deforming or breaking.
See also Properties of metals.
Characteristics of metals
Metals have different characteristics, among which the following stand out:
- Conductivity: metals are good conductors of electricity, which is why they are widely used in the manufacture of cabling, among others.
- Color: metals are usually grayish in color, however, in the cases of pure metals other colors can be observed such as yellow in gold, pink in bismuth or reddish in copper.
- Reuse and recycling: a large number of metals can be recycled and reused, so they can be used more than once and avoid a higher percentage of environmental pollution.