Ndfeb magnets, often referred to as simple NdFeb magnets, are also often the most powerful through a wide range of processes that use rare earth metals. However, because they are made of iron, they rust when exposed to moisture or water for long periods of time, which also makes them more brittle than other types. Neodymium magnets are used in power tool applications, from spinning DVD discs to motors, neodymium magnets are widely used in the automotive industry, and samarium cobalt magnets or iron boron magnets as automotive magnets are usually selected based on operating temperature and/or corrosion resistance.

Operating temperature: While low-coercive neodymium magnets may begin to lose strength if heated above 176°F (80°C), high-coercive neodymium magnets have been developed to operate at temperatures up to 428°F (220°C) with little irreversible loss. The need for low temperature coefficient in neodymium magnet applications has triggered the development of several grades to meet specific operational requirements.

Corrosion: Ndfeb magnets are prone to corrosion, especially along the grain boundaries of the sintered magnet, this type of corrosion can lead to serious deterioration, including smashing the magnet into small magnetic powder, by adding a protective coating to prevent exposure to the atmosphere to solve this vulnerability, nickel plating or double copper-nickel plating is the standard method, you can also use other metals or polymers and paint protective coatings for plating.

Ferrite magnet or ceramic magnet

Compared with rare earth magnets, ferrite magnets although lower energy consumption, but because of its strong demagnetization ability, corrosion resistance, low price and other advantages, has been widely accepted, it is the most commonly used magnet in most types of DC motors. They're not as powerful as neodymium, but they're a cost-effective option for basic crafts, refrigerator magnets, or storing lightweight items.

Operating temperature: The maximum operating temperature of ceramic magnets is 250°C, and although magnetic losses will be experienced when operating at high temperatures, the losses will recover when the material is lowered to normal ambient temperatures. Operating at very cold temperatures (-20°C) can result in a permanent loss of magnetic strength unless the circuit is designed for such extreme situations.

Corrosion: Ceramic magnets have good corrosion resistance and generally do not require coating or plating.