Many industrial applications utilize permanent magnets. A unique type of permanent magnet used in most of these applications is ceramic magnets. They have an impressive set of features that make them valuable materials. Here, we discuss what ceramic magnets are, as well as their applications in daily life and industrial processes.
What is Ceramic Magnet?
Ceramic magnets, otherwise known as ferrite magnets, are a widespread type of permanent magnets. They are known for their medium magnetic strength and ability to withstand fairly high temperatures. Ceramic or ferrite magnets are mainly composed of strontium carbonates or barium carbonate, and iron oxide.
They are the most affordable, hard markets available on the market today. You most likely have seen them: they are the small, round black magnets we see often. Generally, ceramic magnets are sintered from iron oxide and other essential raw materials, such as strontium carbonate. They are broadly classified into three main categories: permanent, soft, and gyromagnetic ceramic magnets.
Manufacturing Methods for Ceramic Magnets
The preparation of ceramic magnets depends on the category of the magnet being prepared. Soft magnets, for instance, are prepared by the sintering of iron oxide and one or more metal oxides, such as nickel oxide, zinc oxide, magnesium oxide, manganese oxide, strontium oxide, and so on. We can also say that ceramic or ferrite magnets are made by calcining a mixture of iron oxide and strontium carbonate to form a metallic oxide.
Unlike permanent ceramic magnets, the residual magnetic field is infinitesimal or non-existent when the magnetic field wears off or disappears. Hence, they are called soft magnets.
Gyromagnetic ceramic magnets, on the other hand, are magnets or magnetic materials with gyromagnetic properties. They are used extensively in microwave communications. Based on their varying magnetic strength and uses, ferrite magnets can be classified into 5 main groups:
Soft magnets: these are ferrite magnetic materials that can easily be magnetized and demagnetized in weak magnetic fields, such as nickel-zinc ferrite. This type of magnets are used primarily on inductance components like filter core, radio core, tape recording, etc., and they serve as the key material of magnetic recording elements.
Permanent magnet: these have a basic hexagonal structure. Their magnetic properties tend to be permanent, hence the name permanent magnet. They are used extensively in telephones, generators, telephones, loudspeakers, television, etc.
Hard magnet: These are Ferrite hard magnetic materials, which are difficult to demagnetize. You’ll find them in recorders, loudspeakers, and magnetic cores of most telecommunication devices.
Moment magnet: Ferrite moment magnetic materials are magnetic materials with rectangular hysteresis loops. A small external magnetic field typically magnetizes it, and it retains its magnetic property even after the external magnetic field is removed. They are primarily used in the memory cores of various electronic computers.
Ferrite gyromagnetic material: These are magnetic materials with rotary magnetism. They typically have various microwave devices with microwave transmission lines.
Basic Characteristics about Ceramic Magnets
Ceramic magnets find their way into many critical applications (such as their use in moderately high-temperature situations and the making of magnetic separation equipment) because of some of the features and characteristics of ceramic magnets:
Ceramic magnets do not have very high magnetic properties, but they possess medium magnetic strength, making them desirable materials for several processes.
They perform relatively well in pretty high temperatures
They are manufactured in the ring, disc, and block standard shape, but they can also be manufactured in the custom specification. This makes ceramic magnets even more helpful in varying applications.
They do not need to be treated or protected for surface rust. They are naturally resistant to corrosion
They have high intrinsic coercive force
They are hard and brittle
Applications of Ceramic Magnets
They are used in DC brushless motors and DC permanent magnet motors
Found in generators and alternators
Applied in assemblies for lifting, holding, retrieving, and separating
Used in refrigerator doors
Also used in magnetic separation equipment to separate ferrous metal material from non-ferrous metal
Used in microphone speakers and Loudspeakers
Ceramic magnets are very useful magnetic materials, which come in standard sizes and shapes. However, you can always request a custom production, depending on the application you need it for.