Magnetic materials

There are a number of elements that are attracted by magnets, commonly referred to as ‘magnetic’. These are the same materials that can be magnetised to create permanent magnets, Here you can see a list of magnetic elements and minerals:

Magnetic materials are categorised as magnetically hard, or magnetically soft materials. Magnetically soft materials are easily magnetised but the induced magnetism is usually temporary. For example, if you rub a permanent magnet along a nail, or a screwdriver, the nail or screwdriver will become temporarily magnetised and will emit their own weak magnetic field. This is because a large number of their iron atoms are temporarily aligned in the same direction by the external magnetic field.

Like magnetically soft materials, magnetically hard materials can be magnetised by a strong external magnetic field, such as those generated by an electromagnet. The difference being that magnetically hard materials will remain magnetised indefinitely, unless they are demagnetised by an opposing magnetic field, raised above their curie temperature or allowed to corrode. Magnetically hard materials are used to create permanent magnets made from alloys generally consisting of varying amounts of iron, aluminium, nickel, cobalt and rare earth elements samarium, dysprosium and neodymium. The strongest permanent magnets are known as neodymium magnets and are made from an alloy of neodymium, iron and boron. Permanent magnets are difficult to magnetise as unlike magnetically soft materials their atomic magnetic domains aren’t easily aligned but once they are aligned, they remain so indefinitely.