Frequently request Questions around Magnets & Magnetism


Here room answers come many typical questions that human being have about magnets and also magnetism concerning the history, magnetic materials, magnetic properties, magnetic orientation, magnetic poles and more. For an ext technical info around these areas, visit ours Magnetics-101-Design Guide.

You are watching: An iron bar can be made magnetic when

Send united state a inquiry for quote or contact us now for much more information around our practice magnets, and let us know exactly how we can aid with your specialty requirements. Huge inventory of neodymium, samarium cobalt, alnico, ceramic and flexible magnets space also available for on-line purchase at

1.0 A short HISTORY

The old Greeks and Chinese found that details rare stones, referred to as lodestones, were naturally magnetized. These stones might attract tiny pieces of steel in a seemingly magical way, and also were uncovered to always point in the very same direction when permitted to swing freely, exposed by a piece of string, or floating on water. Early navigators supplied these magnets as rudimentary compasses to assist them determine their direction while in ~ sea.

The word "magnet" comes from Magnesia, a district in Thessaly, Greece whereby it is believed that the an initial lodestone was mined.

Over the years, magnets have advanced into the high-strength materials we have actually today. That was found that by producing alloys of miscellaneous materials, one can create comparable effects to those found in organic lodestone rocks, and also increase the level of magnetism.

However, it was not until the 18th century that the first man-made magnets to be created. Development in developing stronger magnetic alloys was an extremely slow till the 1920s as soon as alnico magnet products (an alloy that nickel, aluminum and cobalt) were formulated. Ferrite magnets were arisen in the 1950s and rare-earth magnets in the 1970s. Due to the fact that then, the science of magnetism has actually grown exponentially, and extremely powerful magnetic materials have actually made miniature and powerful devices possible. (top)


What is a magnet?

Magnets deserve to be made by place a magnetic material, such as iron or steel, in a strong magnetic field. Permanent, temporary, and also electromagnets have the right to be developed in this manner.

The atoms developing materials that have the right to be easily magnetized such together iron, steel, nickel, and cobalt room arranged in tiny units, referred to as domains. Each domain, although microscopic in size, has millions the billions that atoms and each domain acts choose a tiny magnet. If a magnetic material is put in a strong magnetic field, the individual domains, i beg your pardon normally suggest in every directions, will slowly swing roughly into the direction that the field. They additionally take over neighboring domains. When many of the domain names are aligned come the field, the material becomes a magnet. (top)

Domains prior to magnetization


Domains after ~ magnetization


What does a magnet do?

Magnets execute the following things:

Attract particular materials, such as iron, nickel, cobalt, particular steels and also other alloys.Exert one attractive or repulsive force on various other magnets (opposite poles attract, like poles repel).Have an effect on electric conductors once the magnet and conductor are relocating in relationship to each other.Have an effect on the course taken by electrically fee particles traveling in cost-free space.

Based on this effects, magnets transform energy from one kind to another, without any kind of permanent loss of their own energy. Instances of magnet functions are:

Mechanical come mechanical, such together attraction and repulsion.Mechanical to electrical, such as generators and also microphones.Electrical to mechanical, such together motors, loudspeakers, charged bit deflection.Mechanical to heat, such together eddy current and hysteresis talk devices.

How space magnets made?

Modern magnet products are made through casting, pressing and sintering, compression bonding, injection molding, extruding, or calendaring processes. When manufactured, magnets regularly need to be more processed by grind or various other machining processes, and then assembled into a next level assembly. Visit our production andassembly web page to learn an ext about our practice machining andassembly capabilities. (top)

Are there different species of magnets available?

There are three types of magnets: irreversible magnets, temporary magnets, and electromagnets.

See more: Kumon Answer Book Level H Math Answers Level H, Get And Sign Kumon Answer Book Level H Math Form

Temporary magnets behave as magnets if attached come or close to something that emits a magnetic field, but lose this characteristic as soon as the source of the magnetic field is removed.

There are countless different species of permanent magnet materials, each through their own unique characteristics. Each material has actually a family members of qualities that have properties slightly various from each other, though based on the exact same composition. (top)

What are permanent magnets do of?

Modern permanent magnets room made of one-of-a-kind alloys that have been found through research study to develop increasingly far better magnets. The most usual families of permanent magnet products today are made out of aluminum-nickel-cobalt (alnicos), strontium-iron (ferrites, likewise known as ceramics), neodymium-iron-boron (a.k.a. Neodymium magnets, or "super magnets"), and also samarium-cobalt. (The samarium-cobalt and neodymium-iron-boron families are collectively known as the rare-earths). (top)

What room Rare earth Magnets?

Rare planet magnets room magnets that are made out of the rare-earth group of elements. The most common rare-earth magnets space the neodymium-iron-boron (neo magnets) and also samarium cobalt (SmCo magnets). (top)

What is a short-lived magnet?

Soft steel and specific iron alloys, such as permalloy (a mixture the iron and nickel) deserve to be an extremely easily magnetized, also in a weak field. As shortly as the field is removed, however, the magnetism is lost. These products make wonderful temporary magnets, like those provided in telephones andelectric motors. (top)

What are electromagnets?

Electromagnets are used when very solid magnets are required. Electromagnets are developed by placing a metal core (usually an iron alloy) within a coil that wire the carries an electrical current. The power in the coil to produce a magnetic field. The strength of the electromagnet depends on the toughness of the electric current and the variety of coils the wire. Its polarity depends on the direction of the present flow. If the existing flows, the core behaves choose a magnet, however as quickly as the existing stops, the magnetic properties room lost. Electrical motors, televisions, maglev trains, telephones, computers, and many other modern-day devices use electromagnets. (top)

What are eddy currents?

These are electrical currents that space induced once a magnetic field moves in relationship to an electrical conductor that has actually been placed within with of the magnetic field. In turn, this eddy currents create a magnetic field that plot to prevent the relative movement of the initial magnetic field and also electrical conductor. (top)

What do magnets cost?

Magnet materials have the right to vary considerably in expense from one come the other. Here is an approximate guide regarding magnet costs: