NdFeB sintered magnets are among the strongest permanent magnets used today. They get their power from the Nd2Fe14B crystal, which gives high magnetic density and good resistance to demagnetizing forces. These magnets are made by carefully controlled powder metallurgy: pure materials are melted in a protective environment, turned into fine powders, and then pressed with a magnetic field to align the magnetic direction. They are then vacuum sintered and heat treated to make the material dense and stable. Grain size, how different phases are spread, and the chemistry at grain boundaries all affect performance, especially at higher temperatures. Techniques like diffusion with heavy rare-earth elements can boost high-temperature performance while keeping rare-earth use efficient. Because they can corrode easily, coatings such as nickel, zinc, epoxy, or multiple layers are often added for protection. These magnets power motors in EVs, wind turbines, automation, medical devices, and other energy-efficient systems.