Metals are one of the most versatile materials in our world. They are recyclable because they retain their ductility even after several processes. In the Philippines, steel bars and old metal parts are sold to junk shops for recycling. Speaking of ductility, metals have other properties which made them extremely useful to mankind. These properties are:
A perfect example of metals’ display of chemical properties is their ability to mix with other elements to create alloys. These variations enhance metals for specific applications. One of the most common alloys is stainless steel. This is a product of iron, nickel and chromium, the latter responsible for giving stainless steel its ability to resist rust and discoloration.
Metals also produce cations every time they shed their outer electrons. These cations react to oxygen then form a barrier that prevents further oxygen molecule penetration. This helps the metal retain its shiny appearance and conductivity for a long time. However, there are some metals that rust rather quickly. Some ways to prevent this are by painting, anodizing and plating.
The physical properties of metals are one of the main reasons why they can be utilized in many ways. These characteristics enable the extensive use of metals in machinery and structure. They are lustrous, hard, have high density and high tensile strength. They also have high boiling and melting points. Thanks to their malleability, metals can be shaped into beams, extrusions, vehicle parts, and fasteners. Metals also possess incredible strength under pressure, stretching, and sheer forces. This makes them ideal for structural purposes in buildings, vehicles, bridges and even sports equipment.
Metals are excellent conductors of both heat and electricity. Their conductivity can be accounted for the electrostatic interactions between each atom and electron cloud. This property increases when temperature decreases. When it reaches absolute zero (-273°C), conductivity becomes infinite. This allows complicated circuits to transmit electricity through long distances. Conduction properties also include resistance to corrosion, wear, and fatigue and temperature. Metals are used in applications sensitive to corrosion like chemical plants, food preparation and plumbing. Wear resistance is crucial for all modes of transportation and machinery. Fatigue resistance enables the use of metals in springs, levers and gears. Temperature resistance makes metals suitable for engines and filaments found in light bulbs.
There are some metals that exhibit ferromagnetic properties. This means that they are easily attracted to the force exerted by a magnet and may even persist after removal of the applied field. Magnetic properties are employed in electric motors, generators and speaker systems for audio equipment.
Metals also display emission properties. This is when they release electrons electrons whenever they are exposed to radiation. This phenomena is harnessed in television screen, electronic devices and instruments. In addition to that, there are some metals, such as lead, that can absorb radiation. They are used for shielding during X-Ray examinations.
Metals are definitely important to mankind. People were able to create and invent devices that made lives easier. Who knows, scientists will discover more properties for the further benefit of mankind.