Hard ferrite, also known as permanent magnet ferrite, is a type of ceramic material made from iron oxide combined with other metallic oxides, such as barium or strontium. It is widely used in various applications due to its ability to maintain a strong magnetic field without the need for an external power source. Hard ferrite magnets are commonly found in speakers, motors, and magnetic separators. These magnets are characterized by their high resistance to demagnetization and relatively low cost. They are often used in situations where a stable magnetic field is required over time. The manufacturing process involves sintering, which gives hard ferrite its durability and strength, making it suitable for both industrial and consumer products.