Arc magnets are a special type of magnet solution for numerous industrial applications. If you need to use a magnet that delivers a high-strength field, using an arc magnet would be a good option to consider. However, you need to have a strong understanding of these magnets before using them for any industrial purpose. Read on and we will share more details with you on arc magnets.
What is an Arc Magnet?
An arc magnet is a permanent magnet with a curved or arched shape. As a result, these magnets produce a strong magnetic field over a large air gap. Traditional rod or block magnets have a straight magnetic orientation. But arc magnets project the magnetic field outward in a semicircular pattern.
One of the benefits of the arched design of an arc magnet is the ability to generate a high magnetic flux density across large air gaps. This refers to the open space that exists between the magnet and a ferromagnetic material where repulsion or attraction occurs. This makes arc magnets an ideal application for numerous applications. A few such prominent applications include:
Generators
Electric motors
Magnetic separation
Scientific instruments
How does an arc magnet produce a magnetic field?
Now you have a basic idea of what is an arc magnet, but how are they made? The magnetic field in an arc magnet originates from the aligned magnetic domains of the ferromagnetic material used during the fabrication process. The domain structure will ensure that there is a north pole on the inner concave surface of the arc. Similarly, the south pole would be on the outer convex surface.
This arrangement helps the magnet to have a strong radical magnetic field. It projects perpendicular to the arc in the direction of the air gap. This field strength peaks across the center axis of the magnet and weakens towards the edges.
Types of Arc Magnets
There are quite a few types of arc magnets available out there. Among those types, permanent arc magnets hold a prominent place. Let's learn more about them in detail.
What is a Permanent Arc Magnet?
Permanent Arc magnets are usually made out of materials such as SmCo and NdFeB. They have fixed magnetic properties that you can't easily turn off. Permanent arc magnet assemblies use multiple magnet segments arranged in a curved housing. As a result, they produce a high strength across larger air gaps.
One of the key benefits of a permanent arc magnet is the ability to offer a high power density. They offer resistance to demagnetization and stable long-term magnetic output. Here are a few of the most prominent applications of permanent arc magnets:
Wind turbine generators
Electric motor drives
Magnetic couplings
Lifting
Separation systems
Properties and Strengths of Arc Magnets
At the time of using arc magnets, you need to have a strong understanding of their properties as well. Here are some of the most prominent properties that you can find in them:
Magnetic Flux Density
Measured in Gauss or Tesla units, indicates how strong the magnetic field is in the air gap. Values range from a few hundred Gauss to over 10,000+ Gauss for high-performance NdFeB arc magnets. Stronger is better for application efficiency.
Curvature
Describes the arc angle or span of the magnet segment, usually given in degrees. Typical standard values range from 90° up to 265°. Larger arc angles project greater magnetic force across wider air gaps.
Dimensions
The size - length, width, thickness - list the outer physical dimensions of the arc magnet or its ferromagnetic housing. Standard lengths range from 25mm to 305mm (~1 inch to 12 inches).
Material Composition
The magnetic alloys used such as NdFeB, SmCo, Alnico, or ferrite. Impacts key performance attributes like flux density and temperature resistance. Modern high-strength neodymium magnets are the most common.
Temperature Resistance
The maximum continuous operating temperature where the magnet can function without losing its magnetic properties through demagnetization. Ranges from 80°C for ferrites to 350°C for SmCo.
Lifespan and Durability
Permanent magnets have inherently long lifespans if not subjected to demagnetization threats. Properly designed assemblies can operate reliably for 10-20 years. Water corrosion is the primary long-term durability concern.
Applications and Uses of Arc Magnets
As you can see in the previous section, there are a few unique properties in arc magnets. Due to the same reason, you can find them in multiple applications. Here's a list of the most common applications of arc magnets.
Motorsports and Vehicle Propulsion
You can find powerful and compact arc magnets within electric motors. These magnets help the electric motors to power up high end electric sports cars. In fact, they play a major role behind the acceleration of these cars. Its not just the cars, but you can find such motors in motorcycles as well.
Generators for Alternative Energy
The curved multi-segment arc magnet assemblies boost power density in wind turbines. You can also find them in tidal electricity generators. Arc magnets are responsible for enhancing the overall performance of these generators.
Medical Applications
When exploring the applications of arc magnets, you can't simply ignore the medical applications. Strong neodymium arc magnets are one of the most prominent components that you can find in MRI machines. These machines are available in almost all hospitals to scan patient anatomy. The arc magnets offer highly accurate results with magnetic resonance imaging. Some other medical applications where you find arc magnets include magnetic bracelets and magnetic necklaces.
Magnetic Separation
Industrial magnetic separators use permanent arc magnets. You can often find these in recycling facilities. These magnets are capable of extracting ferrous metals from waste streams.
Sound Systems
One of the most impressive properties of arc magnets is the ability to create an acoustic field. As a result, you can find them in multiple sound generation applications. For example, you can find arc magnets in speakers, microphones, and alarms. Even the audio system that you have in your car would have an arc magnet.
Household Appliances
You can also find arc magnets in numerous appliances that you have at your home. For example, you can find them on your mobile phone and computer. To be more specific, arc magnets play a major role in the functionality of a DVD ROM. The external speakers of your computer would have these magnets as well.
Scientific Research
Custom electromagnetic arc magnets are quite popular in scientific research. For example, you can often find these arc magnet configurations in physics labs. Scientists use them to conduct material experiments in extremely high magnetic field environments.
Apart from these prominent applications, you can find arc magnets in applications such as wedding corsage badges, and model piling.
Manufacturing Process and Costs of Arc Magnets
When learning what is an arc magnet all about, you need to be aware of their manufacturing process and costs as well. Here's an overview of the manufacturing process in detail.
Raw Materials Used for Manufacturing Arc Magnets
The raw materials used for manufacturing arc magnets include magnetic alloy ingots, alloy powders, composites, and rare earth elements. These materials are often blended and melted into the optimum compositional ratio. It provides a significant strength to the arc magnets.
Fabrication and Casting process
Processes such as sintering powder alloys or melting of spinning ribbons are responsible for creating the essential magnetic microstructures. During the manufacturing process, the manufacturers would magnetize individual segments. Then they will assemble those individual segments into housing units.
The cost of manufacturing arc magnets
The cost of neodymium increased over 10x during the past 20 years. That's mainly due to the export restrictions. It created a significant impact on the cost of arc magnets as well. However, you can still get arc magnets for around $150 to $5,000. It all depends on the size and grade of the arc magnet that you are purchasing.
Getting Arc Magnets from Great Magtech
If you are looking to get arc magnets for your applications, you can do it from us at Great Magtech. We offer the highest grade arc magnets with no compromise in quality. You can also take a look at the certifications we have to get assurance over the quality of the products we offer. If you have any questions related to arc magnets we offer, feel free to get in touch with us. We are more than happy to provide answers and help you with your purchase of arc magnets.
Final Words
Now you have a clear understanding of what is an arc magnet all about. These magnets offer an exponentially scalable magnetic field across a wide air gap. The curved shape of these magnets enhances field strength and concentration. As a result, you can use them for new applications and innovations as well. The strength and properties of arc magnets will continue to increase along with advancements in technology. Just make sure to get them from a trusted supplier to experience the best results with your application.