Manufacturing Processes for Permanent Magnets: Bonding and Emerging Methods Abstract Permanent magnets produce magnetic fields and maintain the field even in the presence of an opposing magnetic field. They are widely used in electric machines, electronics, and medical devices. Part I reviews the conventional manufacturing processes for commercial magnets, including Nd-Fe-B, Sm-Co, alnico, and ferrite [...]
Measuring Magnetic Fields After reading this section you will be able to do the following: Determine how the direction and intensity of magnetic fields can be found. Describe how a field indicator and a Hall-effect meter work. Since it is impractical to measure the actual field strength within the material, all the devices measure the [...]
Circular Magnetic Fields: Distribution and Intensity After reading this section you will be able to do the following: Explain the distribution and intensity of magnetic fields around conductors Explain what the skin effect is As discussed previously, when current is passed through a solid conductor, a magnetic field forms in and around the conductor. The [...]
Longitudinal Magnetic Fields Longitudinal magnetic fields refer to magnetic fields that are oriented parallel to the direction of propagation of a wave or particle. These fields play a crucial role in various scientific and technological applications, including particle accelerators, plasma physics, astrophysics, and magnetic resonance imaging (MRI). In the context of particle accelerators, longitudinal magnetic [...]
Electricity and Magnetism After reading this section you will be able to do the following: Discuss what happens to a compass when a wire with electrical current is near. Describe the relationship between electricity and magnetism. Why does the compass respond when it is near an electrical wire with current flowing through it? We can [...]
Electromagnetic Fields After reading this section you will be able to do the following: Describe the magnetic fields that surround a current carrying conductor. Iron filings scattered in the vacinity of a current carrying wire will reveal a magnetic field perpendicular to the current flow. Magnetic field lines directed out of the page towards the [...]
Exchange Spring Magnet An exchange spring magnet is a magnetic material with high coercivity and high saturation properties derived from the exchange interaction between a hard magnetic material and a soft magnetic material, respectively. Coehoorn et al. were the first able to observe an actual exchange spring magnet.[1] Exchange spring magnets are cheaper than many [...]
The Coming Revolution in MnBi High-Strength Magnets Expensive rare-earth magnets that power high-performance motors could be on the wane within a few years thanks to new materials now emerging from research labs. Motor manufacturers that want to impress engineers often bring up the fact that their high-performance motors use rare-earth magnets. But that may soon [...]
Magnetic Field Characteristics After reading this section you will be able to do the following: Describe magnetic fields in different shaped magnets. Understand the important properties possessed by magnetic lines of force. Magnetic Field In and Around a Bar Magnet As discussed previously, a magnetic field is a change in energy within a volume of [...]
Creation of Magnetic Fields After reading this section you will be able to do the following: Define a magnetic field and explain how it is created. Magnetic Field Creation A magnetic field describes a volume of space where there is a change in energy. As Ampere suggested, a magnetic field is produced whenever an electrical [...]
Magnetic Behavior After this reading this section you will be able to do the following: Perform an experiment to detect what materials are magnetic and explain why you think they are magnetic. Magnetism Just like when the Greeks of the old times discovered the first naturally occurring magnetic stones, or natural magnets, you have been [...]
The Two Ends of a Magnet After completing this section you will be able to do the following: Explain what a compass is and how it is affected by a magnet. Understand how a compass helps us to navigate on the earth. Magnets Most people are familiar with the general properties of magnets but are [...]