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The works 3, 11, 12 are devoted to the issues of construction of the two-dimensional theory of magnetoelastic vibrations of thin electroconductive non-ferromagnetic cylindrical shells in a stationary magnetic field.In the works 11, 12, the three-dimensional problem of magnetoelasticity of thin cylindrical shells is brought to the two-dimensional using the method of hypotheses. Cylindrical Magnet Assemblies Home / Mag-Mate / Magnetic Assemblies / Cylindrical Magnet Assemblies These powerful cylindrical magnet assemblies are available in Ceramic, Alnico and Rare earth magnet material with diameters ranging from 1/4' to 2' and with holding values as high as 172 pounds. Rare earth magnets are extremely powerful yet compact. PLEASE NOTE: Orders Received by 3pm Eastern Ship Today. Order Anytime of Day 1-304-257-1193. Skip to Content. Sign In; Create an Account. STRONG - Includes 1 Neodymium Rare Earth Permanent Magnet Cylinder with an incredible Grade N42 Magnetic Energy, stronger than N40, N38, N35, and a whopping 10x Stronger than the strongest ceramic magnet.

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A bar magnet is often approximated simply as a magnetic dipole with north and south magnetic poles separated by a distance . This is not accurate when the magnet has a significant size, so that magnetic lines of force also emanate from the central portion of the magnet. In this Demonstration, we consider a cylindrical bar magnet of length , radius , and magnetization —the magnetic moment per unit volume, which is characteristic of the ferromagnetic material. The magnetization is assumed to be uniform throughout the volume of the magnet, which neglects slight inhomogeneities and possible deviations from the assumed relation .

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The magnetic induction outside the magnet can conveniently be expressed as the negative gradient of a magnetostatic potential: . For a point magnetic dipole , . This is integrated over the volume of the magnet. It is most convenient to work in cylindrical coordinates: for the source and , , for the field point ( can arbitrarily be set equal to 0, in view of the anticipated cylindrical symmetry). The detailed computation is given in Details below. A simplifying feature is that integration over shows that the problem can be reduced to two magnetic monopolar disks separated by the distance .

For ease of visualization, only the field lines in the medial plane of the magnet are shown. The three-dimensional field can easily be pictured by virtue of the cylindrical symmetry about the axis. The lines of force originate from the north pole on the right and terminate on the south pole on the left. Magnetic-induction magnitudes are not emphasized in this Demonstration, only the geometry of field lines.

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Contributed by: S. M. Blinder(July 2011)
with suggestions by Evangelos Matsinos
Open content licensed under CC BY-NC-SA

Snapshots

Details

The magnetic scalar potential is given by a triple integral in cylindrical coordinates:

which can be interpreted as originating from two parallel, oppositely charged monopolar disks of radius separated by a perpendicular distance . The result can be expressed in terms of elliptic functions with complicated arguments and the expressions for the magnetic field components and are even more complicated. It is much easier to do the computations numerically, taking advantage of Mathematica's very efficient NIntegrate routines.

We thereby obtain:

and

.

Permanent Citation

NdFeB magnets Neodymium-iron-boron (NdFeB), is the strongest and permanent magnet available today. With high remanence, high coercive force, and huge energy. It is easily formed into various shape and sizes, and belong to one of the most widely used magnetic materials. Neodymium magnets like NdFeB magnets are specially created to be suitable for the development of high-performance, compact, and light products. For round shape, the min diameter can be done is 1mm, the max out diameter can be done is 240mm.
We have the advantage of this big size neodymium magnets for sale at great price. Low weight loss product, Low-temperature coefficient product, low deviation angle product, and radial oriented ring magnet are our featured products.
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Our professional team, advanced equipment, and well-trained QC staff, makes NdFeB magnets and neodymium magnets have a very high qualified rate of low deviation angle. It depends on the dimensions and requirements. Low deviation angle product was mostly used in sensor application with big requirement and huge quantity. In order to meet the requirement from clients, we worked together with test equipment company to research and develop full-automatic deviation angle tester, which can be bought and used to inspect magnets in past years, it ensures our shipping product 100% qualified.
Radial oriented ring magnet: Ring magnet magnetized in the radial direction is developed successfully which is using shaping method by new multiple radiation orientation, and meet different requirements of permanent motors.
This type of Neodymium magnets fundamentally changed the past situation where radial ring magnet only relied on the magnetic tile assembly, and hugely improved the performance of the motor. The popular poles including: 2 poles, 4 poles, 8 poles, 10 poles, 12 poles, etc, the number of poles and the skew angle were decided by the magnetizing tooling.
It was widely used in the application of robotics and industry automatic production line, etc.
The advantages of radial ring magnet:

1. They can with fewer parts, simplify the assembly process, easily realize automatic assembly.
2. Out diameter higher precision, better coaxiality and verticality;
3. Flexible to choose different ways of magnetizing include magnetizing poles and angles;
4. Highly reliable, no risk of magnet peel off;
5. A very small air gap, the motor has a smoother operating performance with less noise and vibration.

The Neodymium magnets and especially NdFeB magnets are most often used with generators and motors, such as Linear or Servo motors, Wind power generators, Compressor motors, Automotive drive motors, Instrumentation, Automotive sensors, Medical equipment, Audio equipment, Home theater, Wind turbines or even Magnetic tools, etc.
Ferrite magnets Ferrite Magnets are made of BaO or SrO and Fe2O3 by ceramic processing technology. They are widely used in loudspeakers, motors, electronic car motors, home fitness equipment, and other industry areas.
The products appear in disks, blocks, rings, segments, etc.

Cylindrical Magnetron Sputtering

Ferrite magnets are the least expensive magnetic material and are very corrosion-resistant, so no coating is required.
Ferrite magnets can be created to be anisotropic or isotropic, and the maximum application temperature is 225 °C. It offers a great balance between strength and affordability, it can be magnetized with multiple poles and it also doesn’t easily demagnetize.
Alnico magnets Alnico Magnets are composed primarily of Cobalt, Aluminum, Nickel, Iron, and Copper. It has very good resistance to corrosion and high max working temperature, can reach 550deg.C.
Even if other materials offer higher energy and coercivity values, the huge remanence and thermal stability of Alnico magnets make it the ideal cost-effective material for certain applications, like microphone lifting, generator, voltmeters, and measuring instruments.
Alnico magnets are widely applied in high stability fields as military, aerospace, automobiles, and security system. The max working temperature can reach 550deg.C.

Cylindrical Magnets

Alnico magnets have been in production since the 1930s and predated the discovery and manufacturer of almost all earth magnets (including samarium cobalt magnets and neodymium magnets).
Though alnico magnets have largely been replaced by stronger neodymium magnets like NdFeB magnets and Smco magnets they are still widely used in the manufacturing of sensors, guitar pickups, loudspeakers, and many other everyday household objects.

Cylindrical Magnet

Samarium cobalt magnets:
Samarium cobalt magnets (SmCo) are resistant to max working temperatures above 300° C, so they remain stable at temperatures far above the Curie point of materials like NdFeB magnets; Corrosion-resistant; Proven in applications where big performance and efficiency are required, such as those in the automotive, motorsport, aerospace, and defense industries.
All rare magnets like Neodymium magnets, including Samarium cobalt magnets (SmCo) are very powerful. They have the capacity to function in high temperatures and have very good resistance to corrosion. Like many other rare earth magnets, samarium cobalt magnets are brittle and can be chipped and cracked very easy making them unfitted for applications that need to repeat direct impact to the surface of the magnet.
This high performance and big-temperature magnet is usually used in the food and industrial manufacturing industries. Samarium cobalt magnets were one of the first types of rare magnets and have now been commercially available for almost 40 years. Since Neodymium magnets have been discovered and made commercially available on sale at great prices like we have on our website samarium cobalt magnet is still the first choice magnet for adverse or high-temperature environments.

Cylindrical Magnetic Field

Pot magnets: Pot magnets consist of a steel shell with a magnet sunken into one face, which design gives many advantages; pot magnets can be supplied with a countersunk hole, a straight hole, a threaded stud, or a threaded collar or a screw hole. The main Magnetism is confined to one face, where it is concentrated to give the maximum holding force possible for the size of the magnet. Pot magnets are resistant and don’t crack or chip with constant impacting onto a steel surface which is a very big advantage.

Hollow Cylinder Magnet

The pot magnets can be provided with hooks and eyebolt attachments, which are perfect for hanging a variety of items.