What are the main magnetic materials? What are the types of common magnetic materials?
The most commonly used magnetic materials are the following three: ferrite, neodymium, iron, boron and samarium, cobalt, permanent magnets. Ferrite and samarium-cobalt magnets are not subject to corrosion and, as a rule, are rarely surface coated. However, NdFeB magnets are brittle and their surface oxidizes easily, so electroplating is required to prevent corrosion. NdFeB and SmCo contain rare earth elements, so they are commonly referred to as rare earth permanent magnets. #permanent magnet#
Ferrite magnet1. Ferrite magnet
Ferrite magnets, also known as ceramic magnets, are a kind of rare earth materials for permanent magnets. They are composed of compounds composed of ceramic materials and iron oxide. Although ferrite magnets are made up of various chemical elements, the entire main component is the iron oxide category. Both types of ferrite magnets contain their own unique elements, with approximately 90% of the material being iron oxide.
Ferrite magnets are very strong and durable, but they are weaker than conventional neodymium magnets, which are more versatile.
Ferrite magnetic material is a functional material with a wide range of applications, which is one of the main materials in today's electronics industry.
NdFeB magnet2. Magnet NdFeB
NdFeB magnets were invented in the 1980s. It is the strongest rare earth magnetic material, consisting of an alloy of neodymium, iron and boron. Neodymium magnets can be used in many applications where large magnetic fields or smaller magnets are required, such as motors, electronic devices, hardware accessories, etc.
The magnetic field strength of NdFeB magnets is the strongest among permanent magnets. Compared to samarium-cobalt magnets, neodymium magnets have higher coercivity but lower Curie temperature and are more easily oxidized by air. To avoid corrosion, the surface of neodymium magnets must be protected during use, such as gold plating, nickel, zinc, tin or epoxy on the surface.
SmCo magnet3. Samarium Cobalt Magnet
Samarium-cobalt magnets are made from samarium, cobalt and other metallic rare earth materials by dosing, melting into alloys, crushing, pressing and sintering. Samarium-cobalt magnet is the earliest discovered rare earth magnetic material. SmCo magnets have two composition ratios, namely 1:5 and 2:17. Samarium cobalt magnets on the market are mainly 2:17 samarium cobalt magnets.
SmCo magnets have high magnetic energy product and low temperature coefficient, and the maximum working temperature can reach 350℃. When the operating temperature exceeds 180°C, its maximum energy product (BHmax), coercive force, temperature stability, and chemical stability exceed those of NdFeB magnets. Samarium cobalt magnets are highly resistant to corrosion and oxidation. The maximum energy product (BHmax) of samarium-cobalt magnets ranges from 16MGOe to 32MGOe, and its theoretical limit is 34MGOe.
Due to the high cost of samarium cobalt magnets, there are relatively few applications.
The above content is an introduction to common magnetic materials. In terms of applications, NdFeB magnets are the most widely used. In terms of high temperature resistance, samarium cobalt magnets have advantages, and the requirements are not high. in pursuit of cost, you can choose ferrite. If the above content is useful to you, please like, comment and pay attention.