Magnetic Properties Of Ferrite Magnets

Ferrite magnets, also known as ceramic magnets, provide the lowest magnetic field strength of all permanent magnetic materials with a maximum energy product range of 0.8-5.3 MGOe. However, they are by far the most cost effective to manufacture in large volumes, which is a reason why they are commonly used for commercial, high volume production runs where space, and therefore the size of the magnet is not a limiting factor.

Ferrite magnets can generally be manufactured in individual blocks as large as 152mm x 101mm x 25mm (6in x 4in x 1in). There are two types of ferrite magnets manufactured today, strontium ferrite (SrO.6Fe203) and barium ferrite (BaO.6Fe203). Strontium ferrite is the most popular as they provide the best magnetic properties.

Below, you can see a list of all the commercial available strontium ferrite magnet grades and their magnetic properties.

Unfortunately, there are different naming standards used in different markets. The above ‘Y’ nomenclature is a Chinese standard, and the most widely used. Less regularly used are the ‘C’ American nomenclature and the ‘HF’ European standard. The magnetic properties of each of the standards are comparable. If you are more familiar with the American or European standard, you may find the following quick reference guide useful.

Quick cross reference:-

C5 = Feroba 2 = Fer 2 = HF26/18 = Y30

C8/C8A = Feroba 3 = Fer 3 = Y30H-1

C1 = Y8T / Y10T

C7 = Y26H-2 C8B = Y33

C9 = Y30H-2

C10 = Y33H

C11 = Y34

C12 = Y30H-2

Ferrite magnets are non-conductive and will not corrode as they are essentially already made from rust (iron oxide) and therefore cannot corrode further. They also maintain their performance in high temperatures and can be used in temperatures up to 250 degrees Celsius before any loss in performance occurs.

However, ferrite magnets are susceptible to demagnetisation by stronger magnetic fields, which is why you will not find rare earth and ferrite magnets working together in the same application. Uniquely, their resistance to demagnetisation actually improves as the working temperature rises to make them particularly useful for electric motors.

Ferrite magnets are typically produced in standard shapes such as discs, arcs, blocks and rings rather than some of the more intricate shapes that you will find rare earth magnets produced in. At Magnet Expert Ltd we have the capability to produce bespoke ferrite magnets; however, tooling charges for bespoke ferrite magnets are often high due to the nature of the material and the manufacturing process. If you have an enquiry about ferrite magnets please give our experts a call today on 0800 488 0288.