When shopping for magnets, you may come across the term “temporary magnets.” All magnets produce a magnetic field that forces electrically charged particles to move in a helical field around the magnet — and temporary magnets are no exception. They produce an invisible field that attracts and repels other magnets. Temporary magnets, however, aren’t the same as permanent magnets.
Overview of Temporary Magnets
Temporary magnets are characterized by their ability to stop producing a magnetic field. As their name suggests, they don’t produce a magnetic field all the time. Rather, temporary magnets only produce a magnetic field when exposed to an external magnetic field or when there’s an electric current running through them.
How Temporary Magnets Work
There are different types of temporary magnets, such as soft iron and electromagnets.
Soft iron temporary magnets work by aligning their atoms when exposed to an external magnetic field. Their atoms aren’t aligned all the time; only when a magnet is pushed near a soft iron will its atoms become aligned, resulting in a magnetic field. Conversely, when the external magnetic field is removed, temporary magnets will stop producing their magnetic field.
Electromagnets work in a similar way, but they require an electric current. Electromagnets consist of a core — typically an iron core — that’s wrapped in a coil of wire. When an electric current runs through the wire coil, the core will become magnetized. Its atoms will become aligned, allowing the core to produce a magnetic field.
Benefits of Temporary Magnets
Temporary magnets offer several benefits. Soft iron magnets are inexpensive and versatile. They are commonly used in recycling, sorting and material handling applications. Since they are made primarily of iron, they cost less than other types of magnets, such as rare earth magnets.
Electromagnets are capable of producing a very strong magnetic field. The core amplifies the magnetic field as an electric current runs through an electromagnet.
In addition to being strong, electromagnets can be turned on and off. They will only produce a magnetic field when an electric current is running through them. Therefore, electromagnets are an excellent choice for applications like medical imaging, electric relays and industrial lifting.
In Conclusion
Magnets can be categorized as permanent or temporary depending on the state of their magnetic field. Permanent magnets have a magnetic field in a permanent state, meaning they always produce a magnetic field. Temporary magnets, on the other hand, have a magnetic field in a temporary state.