Powerful magnet refers to an object or material that can generate a magnetic field. It is usually made of metal alloy and has strong magnetism. Traditionally, it can be divided into "permanent magnets" and "non-permanent magnets".Permanent magnets can be natural products, also known as natural magnets, or they can be manufactured artificially (the strongest magnets are neodymium iron boron magnets).Non-permanent magnets sometimes lose their magnetism.The ancient Greeks and Chinese found a kind of naturally magnetized stone in nature and called it "magnetite". This kind of stone can magically suck up small pieces of iron, and it always points in the same direction after swinging at will. Early voyagers used this magnet as their earliest indicatorThe compass is at sea to tell the direction.After thousands of years of development, magnets have become powerful materials in our lives today. By synthesizing alloys of different materials, the same effect as the magnetite can be achieved, and the magnetic force can also be improved. Artificial magnets appeared in the 18th century, but those made of stronger magnetic materialsThe process was very slow, until Alnico was produced in the 1920s. Subsequently, ferrite was manufactured in the 1950s, and rare earth magnets were manufactured in the 1970s [Rare Earth magnet includes neodymium iron boron (NdFeB) and samarium cobalt (SmCo)]. So far, magnetic technology has developed rapidly, and strong magnetic materials have also made the components more compact.Most magnetic materials can be magnetized to saturation in the same direction, which is called the "magnetization direction" (orientation direction). Magnets without orientation direction (also called isotropic magnets) are much weaker than oriented magnets (also called anisotropic magnets).
