GEOLOGY

Detailed explanation-1: -In permanent magnets, a property called coercivity is present, which means they can withstand being demagnetized without becoming weak. Materials such as Sm-Co and Nd-Fe-B have high coercivities, in contrast to older materials like Alnico or ceramic materials [hard ferrite].

Detailed explanation-2: -At a temperature called the Curie point – this varies in different metals, but it is around 770° in iron – permanent magnetism is lost altogether. Over a longer period of time, random temperature fluctuations, stray magnetic fields and mechanical movement will cause magnetic properties to decay.

Detailed explanation-3: -PERMANENT MAGNET TYPES The five types of permanent magnets are alnico, samarium cobalt, ferrite, flexible rubber and the strongest permanent magnets, neodymium magnets.

Detailed explanation-4: -A permanent magnet is an object made from a material that is magnetized and creates its own persistent magnetic field. As the name suggests, a permanent magnet is ‘permanent’. This means that it always has a magnetic field and will display a magnetic behavior at all times.