What Types of Magnets are Used in Vehicles

What are the different Varieties of magnets used in automobiles or vehicles?

Magnets are the materials or magnetized particles of iron ore that generate a magnetic field (invisible property of the magnet). Due to magnetic field property, the magnets can pull the ferromagnetic materials (cobalt, nickel, steel, and iron) and they can repel or attract the other magnets available in the universe. The electromagnet and permanent magnets are the major types of the magnets. The electromagnets are made of a coil of wire wrapped around the ferromagnetic material. The electromagnets are the temporary magnets and retain their magnetic strength until the flow of current in the coil of wire continues. The permanent magnets are the magnets that have a permanent and strong magnetic field.  The magnets are commonly used in vehicles making the operation and functions comfortable, safe, and efficient. The entertainment parts, motor parts, sensors, and safety components of the vehicles are made up of natural magnets or artificially made magnets. The different properties and characteristics like thermal stability, resistance to corrosion, magnetic strength, and cost saving of the magnets are analyzed and considered for the right selection of the magnets for the applications in the automobiles. The magnets (Ferrite magnets, SmCo magnets, and rare earth neodymium magnets) generally used in the manufacturing of Automobiles or vehicles are studied and described in this article.

Ferrite Magnets:

    A Ferrite magnet is a iron oxide magnet having ceramic magnetic elements and is magnetized to a permanent magnet when interacting with the magnetic field.  These magnets are produced by mixing the metallic elements with iron oxide. The ferrite magnets are economical and highly resistant to corrosion and demagnatism but have lower magnetic strength and power than the NdFeB (Neodymium magnets). These magnets are not demagnetized due to their high coercivity properties. The ferrite magnets are available in dark gray or black color in the markets and are widely used for applications where economical magnets are required compromising the magnetic strength and performance.

 The relay of an automobile or vehicle is a switch device that is used to connect and disconnect the electric circuit and magnetic sensors control the motor and detect the position of the vehicles.  The ferrite magnets are widely used in these critical parts of the vehicles for efficient operation. The ferrite magnets are used in these components because of their economical and long-lasting properties. The ferrite magnets are used in the motors of the vehicles for operation of seat adjustment, window, and driving the fuel pumps. The speakers used in the vehicles for music and other alarming systems also have the ferrite magnets. These magnets are very resistant to corrosion and also suitable for the different temperature conditions or environment because of stability nature against the high temperature and hot environment.

Neodymium ( NdFeB) magnets (Rare Earth):

Neodymium magnets are permanent magnets produced by alloying boron, Iron and Neodymium elements and available in different shapes like bar, ring, countersunk, block and disk in markets. These magnets are widely used in different sectors due to strong magnetic strength, corrosion resistance, and stability towards diamagnetism.  The applications where a strong magnetic field is required in pact or most compact form, the permanent Neodymium magnets are mostly preferred. The Neodymium magnets produce strong magnetic field due to high energy density and that is the reason are considered for the production Automobiles/ vehicles. Neodymium magnets are widely used in sensors, actuators, entertainment devices and motors of the hybrid vehicles and electric vehicles. The performance and efficiency of the hybrid and electric vehicles are increased by using the permanent magnets in the motors because they make the operation of the motor smooth and less independent of the energy source. The magnets are used in regenerative braking systems of the vehicles which stores the brake energy and fulfills the needs of energy for lighting and other energy purposes of the vehicles. The need of Neodymium magnets has been increasing in the automobile industry due to the maintenance of strong magnetic field in the compact size components.

Samarium Cobalt Magnets:

Samarium cobalt magnets are permanent magnets rare earth magnets and produced by the combination of cobalt and samarium materials. These magnets are famous for their high resistance to corrosion and stability to high-temperature conditions or environments. These magnets show better performance in high-temperature environments but has a weaker magnetic field as compared to the Neodymium Rare Earth magnets. These magnets can retain their magnetic field to a temperature of more than 350 centigrade. These exceptional properties have made the magnets more demanding than other magnets for manufacturing of Automobiles.

The Samarium cobalt magnets are expensive and that is main reason that they are used in the components that perform specific or limited functions or operations. These type of magnets are widely used in special vehicles like luxury cars and sports. The sensors and actuators of the braking and engine sections have samarium cobalt magnets because of their stability to high-temperature conditions. There are some risks related to continuous performance with the use of these magnets in high-temperature atmospheres.

Alnico magnets:

Alnico magnets are the type of permanent magnet produced by combining the cobalt, nickel, and cobalt elements. The Alnico magnets have a strong magnetic field and high thermal stability properties. These magnets are highly resistant to corrosion and can last for a longer time. The Alnico magnets are used in speakers and ignition section of the vehicles.

Magnets in Vehicles

The types of magnets described above are selected for the vehicles based on required properties and consideration for the design of components used in the vehicles. The important application of magnets in the vehicles are described below:

Entertainment devices: The sound in the entertainment devices like speaker, Audio and Video Tvs is produced with the help of magnetic field of the magnets. The magnetic field of the magnet interacts with electric current and produces the electromagnetic force and this force helps the driver of the speaker move back and forth. The sound is produced with the interaction of voice call motor with the magnetic field and type of the magnet decides the quality of magnetic field. Ferrite magnets are generally preferred for the speakers and audio devices.

Magnetic motors:  The torque and driving force of the motors of hybrid and electric vehicles are produced by the permanent magnets. The permanent magnetic field interacts with the magnetic field produced by electricity and drives the rotor of the motor. Neodymium magnets are used in the motor of vehicles.

Safety components:  The safety systems of the vehicles are airbag actuators and wheel speed sensors have the samarium cobalt magnets.  The speed of the wheel of the vehicle is detected by the magnetic sensors known as wheel speed sensors. The wheel speed sensors or ABS controller are permanent magnet consisting of wire of coil wrapped on a core made up of metal. When rotation of toothed ring crosses the tip then there is a change in the magnet flux lines produced by the sensors and voltage pulses are generated.

Accessories (Power):  The ferrite magnets are used in the driving motor for the door, seats, mirrors, and windows of the vehicle. These magnets are economical and have stable performance for different conditions.

Actuators and sensors: The sensors are basically the monitoring components of the vehicles which observe all the factors and display the variations. The speed, proximity, acceleration, and temperature are the variables of the vehicle observed by the sensors. After gathering the data of these variables the sensors are shared with the control system of the vehicle. The actuators are the active parts of the vehicle system. The actuators respond concerning the received signals from the control system. The apply of brakes, variation of fuel in the engine and arrangement of the suspension system are done with the help of actuators. The electrical information obtained from the control system is converted into mechanical operation through actuators. The functions of the actuators and sensors are controlled by the magnetic field of the samarium cobalt magnets and ferrite magnets. The fuel control, brake and steering mechanism are governed by the magnetic sensors and actuators.

The magnets are major components of the systems of the Vehicles and suitable selection of these magnets for specific operations is based on the specific characteristics and considerations. The exceptional magnetic strength of the rare earth Neodymium magnets has made these magnets most important for the functions of the braking (regenerative) and motor of the vehicles. The ferrite magnets are reliable and economical magnets due to which these are very suitable for the power accessories of the vehicles. The SmCo magnets have ideal thermal stability due to this, these are used in high-temperature conditions or environments.  The other magnets have lower thermal stability than the SmCo magnets. The characteristics of the different magnets used for the vehicles are described in this article.  The importance of magnets for the automobile industry is increasing due to the advancement of technology. Vehicles are becoming reliable, efficient, and innovative with the advancement of technology.