Professional in producing ring ferrite magnets, Young Magnet is one of the best manufacturers and suppliers in China. We have quality ring ferrite magnets for sale. Please feel free to contact us. Speaker magnets: 1) low cost 2) hard and brittle 3) require specialized machining techniques Ring...
Product Description of Ring Ferrite Magnets
These ring ferrite magnets are made of quality pressing and sintering of strontium and iron oxide with high performance, which is durable and reliable. Equipped with beveled edges, our product could make separating the magnets a snap, and discourage damage to the magnets. And the hole allows objects to be attached easier. The nice round surface attractive magnets have a north and south pole side pull and repel.
As a matter of fact, they can also be used at fairly high temperatures. In addition, the compact design can fit any kind of occasion. Due to the proper size, these ring ferrite magnets can be widely used in totally different fields, and they are all available for education, science, kitchen, office, building, creativity, craft and so on.
Product Feature
These ring ferrite magnets are equipped with high resistance to demagnetization, corrosion and oxidation.
There is no marks or stains while removing from the board, which is easy to move.
Our product is an ideal item in your daily life, and it is available for crafting, jewelry, office boards, and DIY magnets.
We do promise that it will never break or fall down even if there's an earthquake.
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Shape
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Block/Rectangle/Square
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Disc/Round/Cylinder
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Ring/Countersunk
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Dimension
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L (?) x W(? ) xT(?)
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D(?) x T(?)
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OD(?) x ID(?) x T(?)
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L: length. W: width, T: thickness, D: diameter, OD: outer diameter, ID: inner diameter.
For other shapes, please tell more in details or drawing would be much appreciated.
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Coating
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Zn, Nickel, Ni-Cu-Ni, Epoxy, Au, Silver or other ?
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Working Temperature
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Normal or High temperature ?
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Advantages & Disadvantages of Ferrite (Ceramic) Magnets
Do not corrode in water.
Can be used up to +250 degrees C (482F)
Sometimes up to +300 degrees C (572F) in special circumstances.
High coercivity (Hci) that increases as magnet heats up.
Electrically insulating.
Relatively low cost - good for cost saving projects.
Common Products Specification
50mm outer diameter x 25mm inner diameter x 10mm thick.
1.97 in. outer diameter x 0.98 in. inner diameter x 0.39 in. thick.
Each magnet's north and south poles are on opposite circular faces.
Each magnet can support 4kg (8.82lbs) pull vertically from the magnetic face when in flush contact with a mild steel surface of equal thickness.
Resistant to demagnetisation and corrosion without any extra coating.
Standard Dimensional Tolerances for Ring Ferrite Magnets
Here are the standard dimensional tolerances for ceramic ring magnets based on the following dimensions:
+/- 0.005" on OD & ID dimensions ranging from 0.040" to 1.000".
+/- 0.010" on OD & ID dimensions ranging from 1.001" to 2.000".
+/- 0.015" on OD & ID dimensions ranging from 2.001" & above.
How to Make Magnetized Ferrite?
The following is a general overview of the process used in industrial manufacturing:
Mixing Raw Materials
The first step involves thoroughly mixing the iron oxide and the chosen carbonate material, along with any additives, to create a uniform powder mixture. The proportions of these materials are carefully controlled to achieve the desired magnetic properties.
Forming the Magnet Shape
The mixed powder is then pressed into the desired shape using a hydraulic press. This process can create various magnet shapes, such as discs, blocks, or custom shapes.
Sintering
The formed magnets are sintered in a high-temperature furnace. During sintering, the magnets are heated to temperatures above 1,000 degrees Celsius (1,832 degrees Fahrenheit) in a controlled atmosphere. This process fuses the particles together and transforms the mixture into a solid, crystalline structure.
Cooling
After sintering, the magnets are slowly cooled to room temperature to prevent thermal stresses and cracking.
Magnetization
Once the magnets are fully formed and cooled, they are exposed to a strong external magnetic field. This process aligns the magnetic domains within the material, giving the magnet its magnetic properties. This step is typically performed using specialized equipment that can generate the required magnetic field.
FAQ
Q: 1.Can you cut into ferrite/ceramic magnets to alter their shape?
A: While it is not recommended to cut or alter ferrite and ceramic magnets, it can be done if you proceed carefully. Since this type of material is very brittle and fragile, the best way to go about separating it is to slowly and precisely drill through both sides, flushing out the holes as you go.
Q: 2.Are permanent magnets also considered to be rare earth magnets?
A: Rare earth magnets and permanent magnets are technically the same things. Both neodymium magnets and samarium cobalt magnets are considered to be under the rare earth category, which is both classified as permanent.
Q: 3.What is the strongest type of permanent magnet?
A: The strongest type of rare earth or permanent magnet is the neodymium magnet. Anything that contains this element as the main ingredient will have an incredibly strong magnetic force that can withstand almost anything and will last for several years.
Q: 4.Which magnets are the strongest?
A: Neodymium Magnets are the most powerful choice on sale for the general public. Stronger than Ferrite Magnets but more expensive. They are graded from N28 to N55 according to their strength.
Q: 5.What do the N28, N30, N35, N38, N40, N42, N48, N50, N52, N55 tags mean on Neodymium Magnets?
A: On Neodymium Magnets the letter N followed by a number (usually from 28 to 55) rapresents the grade (magnetic strength) of the magnet, which is linked to the magnetic flux output per unit of volume. The higher the value, the stronger the magnet. For reference, a small N45 3 x 2mm Neodymium disc has an adhesive force of 0,18 Kg, whereas a N48 has 0,25 Kg (39% more !!!).
Q: 6.Which Magnets are more resistant to high temperatures?
A: Ferrite Magnets are the go-to solution for heat resistance. They can withstand up to 180°C without issues for magnetic strength or durability.
Neodymium Magnets are fine at room temperature, but their performance suffers when temperature rises. Above the 100 °C threshold, their force decreases drastically until ceasing completely after the 320 °C limit. Special alloys can be used to curb this fall (although they are really expensive and designed for special applications). A Neodymium Magnet exposed to temperatures above 80°C will incur in a permanent loss of performance, this will happen to a smaller degree for standard Ferrite Magnets, too, but only when the temperature exceeds 180°C. Special Alnico and Samarium Magnets can withstand much higher temperatures of 525 and 650°C respectively.
Q: 7.Which magnets are more resistant to corrosion?
A: Ferrite Magnets are very resistant to corrosion. They are made with iron oxide, and, as a result, they do not corrode even when submerged in water. Neodymium Magnets tend to be more vulnerable to corrosion. To prevent magnet's deterioration, a protective coating can be added, usaully Nickel or Copper-Nickel plating, or a plastic polymer coating.
Q: 8.Which magnets are the cheapest?
A: Ferrite Magnets are the cheaper option for commercial magnets. Neodymium Magnets are more expensive (but stronger), mainly because of their rare-earth elements composition and manufacturing process. For reference, a 40x20x10mm Neodymium N35 Nickel coated block can cost you 5 euros, while a Ferrite Magnet of the same size costs less than 1 euro.
Q: 9.Should I buy Ferrite or Neodymium Magnets?
A: It really depends on your needs. Neodymium Magnets look shiny, smooth and metallic. They are more powerful, but also more expensive. Furthermore, they are more susceptible to corrosion, oxidation and high temperatures.
Ferrite Magnets look darker and unpolished. They are the cheapest commercial magnets and excel for their high resistance to heat and corrosion.
Q: 10.What are the uses of ferrite ring magnets?
A: They are used to make permanent magnets for applications such as refrigerator magnets, loudspeakers, and small electric motors. "Soft" ferrites have low coercivity, so they easily change their magnetization and act as conductors of magnetic fields.
Q: 11.What is the difference between ferrite magnet and neodymium?
A: Ferrite magnets have a higher Curie temperature than Neodymium magnets, so they maintain their magnetization better at higher temperatures. This gives designers greater operating margins at higher temperatures than Neodymium magnets offer.
Q: 12.What is ring ferrite?
A: Ferrite ring cores are doughnut-shaped or cylindrical-shaped ferrite pieces. The purpose of ferrite ring cores is to suppress noise present in the circuit without grounding.
Q: 13.What are ring magnets used for?
A: Neodymium ring magnets are used in applications such as loudspeakers and stereo systems, motors and sensors used in automotive and other high-tech, high-value applications, and in technology such as generators that ensure critical electronic equipment stays running in places such as hospitals during power outages.
Q: 14.When to use a ferrite ring?
A: Ferrite rings are employed in circuits or inserted in cables to: Suppress EMI: Ferrite beads block the high-frequency signal emissions and absorption associated with cables, helping to suppress electromagnetic interference.
Q: 15.Are ferrite magnets safe?
A: Due to the force exerted by the magnets it is possible that chips may fly off at high speed into someone's eye, therefore we advise that when handling more than one ferrite magnet that you wear eye protection. Chips and broken magnets can also be quite sharp, so treat them as carefully as you would broken glass.
Q: 16.Is a ring magnet permanent?
A: Their high permeance coefficient makes Neodymium Rings ideal for a range of magnetic applications. These types of permanent magnets can be used in science projects or experiments, medical applications, cabinetry, water conditioning, loudspeakers, and much more.
