What are Dielectrics?

Dielectrics have zero or deficient electrical charge. They are also called non-conductors because they do not allow the current to flow easily; hence they cannot be charged. This feature makes them useful in different industries. 

Dielectrics  are insulating materials because they do not conduct current. They are ubiquitous in capacitors, transformers, and loudspeakers.

Importance of dielectrics in different industries

There are different industries where dielectrics can be used, including the construction and communications industries. In the construction industry, dielectrics can be used as insulation for electrical wires, protecting them from heat. 

They are accommodating in the communications industry because:

• They provide high electrical resistance.
• They are ideal capacitors.
• They can be used as transformers.
• They can be used for loudspeakers.

Functions of dielectrics

Dielectric materials have significant importance in electronics, insulation, and dielectric heating. Their functions include:

1) Insulation: This function is carried out by dielectric material with high permittivity. The combination of high permittivity and low conductivity makes it an effective insulating material, making them useful for different industries.

2) Dielectric heating: Dielectric heating is done by a high voltage alternating electric field applied to an insulating material. The electric field generates long range forces in the insulating medium. These forces cause the molecules to reorient themselves in such a way that they stress the lattice and produce heat. This process can be used in high-power devices like microwave ovens, radio frequency (RF) generators, and shortwave transmitters. Dielectric heating is also used for soldering, forming composites, and converting solids to liquids. Dielectric materials are made in a skinny layer. When a small amount of current passes through it, it heats up. Dielectric heating is an important function in the field of dielectrics, especially for heating and cooling systems.

3) Electronic components: The combination of high permittivity and low conductivity makes it one of the best materials for electronic components like capacitors, resistors, inductors, etc. These components allow us to manufacture various electronic products such as computers, televisions, and other consumer products.

4) Signal transmission: This function is important for communication in vacuum becaxue vacuum has a high permittivity and low conductivity. This property allows it to be used in capacitors. 

The signal can be conducted by means of electronic conduction through the use of a transmission line. These circuits have good electrical insulation and high stability. These materials are also used for matching networks, filters, etc. Matching network is an important part in wireless communication systems like satellite phones and cell phones. 

The combination of high permittivity and low conductivity make them suitable for matching as well as tuning circuits, klystrons, cavities for microwave spectroscopy, etc. 

5) Heat transfer: Dielectrics are also used to transfer heat from one place to another. For example, they are used with convection surfaces to generate an air conditioner or thermal insulation material. In these instances, the heat is transported by convection, and the convection surface moves heat from one place to another.

6) Electrical insulation: When the electrical properties of this material are measured, it turns out that it has a high permittivity. This permittivity makes the separation between the electrical path and ground of the metal parts and other components.

7) Magnetic shielding: At high frequencies, dielectric material has a high permittivity and low density. This combination makes it useful for magnetic shielding for such things as x-rays, gamma rays, etc. Dielectrics are used to shield the magnetic field of the components.

8) Static charge balancing: Static charge can be a big problem in electronics, and dielectric materials are used to balance the static charges because of their low conductivity.

Types of dielectrics

Polar dielectrics

These are materials that have the ability to conduct or convey electric charges. They are called polar dielectrics because they have the capacity to polarise in an electric field. They have a positive and negative side, so their electrical charges are positive on one side and negative on the other. Polyethylene is one example of a polar dielectric. They are used in applications that require a flat surface and polarisation like in cellphones and tablets, and they have also been used in transparent conductive film (TCF).

Non-polar dielectrics

These are materials whose electrical field is perpendicular to the direction of polarisation. It is mainly used for construction purposes.

Mixed oxide materials

These form a mixture of oxides with metals used for different purposes. For example, titanium dioxide (TiO2) has dielectric properties that differ from natural ores or cobalt oxide (CoO).

Significance of dielectrics

Dielectrics are helpful in various functions. For example, they are used in insulating electronic devices, signal transmission, and heat transfer. 

It can be inferred from their name – dielectric materials are found everywhere, and the most common examples include plastic and wood. For example, a high-permittivity wire is generally made of plastic, such as Teflon or Viton. In addition to that, the air surrounding us is also a dielectric material with a permittivity of around 1.

Application of dielectrics

In the communications industry, dielectrics are essential because there would be no way to deliver information and produce sound without them. They are used by the telephone and broadcast industries.

Without dielectrics, there wouldn’t be any sound produced from a loudspeaker because capacitors convert the stored electrical into sound. Dielectrics are also used in transformers for changing the voltage of electricity. 

In telecommunication, dielectrics are used for insulating wires for heat protection and other damaging factors.

Conclusion

We can conclude that dielectrics are very important in our daily lives. They are widely used in various functions such as insulating, heat transfer, etc. The properties of dielectrics are unique, and we have seen the functions that they carry out for both characterisation and application. They play an important role in various industries, so it is necessary to understand these materials.