Frequently inquiry Questions around Magnets & Magnetism

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

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1.0 A brief HISTORY

The old Greeks and Chinese discovered that details rare stones, dubbed lodestones, were naturally magnetized. This stones could attract little pieces of iron in a seemingly wonder way, and were found to always point in the very same direction when permitted to waver freely, rely by a piece of string, or floating top top water. Early on navigators offered these magnets together rudimentary compasses to aid them recognize their direction while at sea.

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

Over the years, magnets have progressed into the high-strength products we have today. That was uncovered that by developing alloys of miscellaneous materials, one can create comparable effects come those found in natural lodestone rocks, and increase the level of magnetism.

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

2.0 THE BASICS

What is a magnet?

Magnets can be make by placing a magnetic material, such as iron or steel, in a strong magnetic field. Permanent, temporary, and also electromagnets can be produced in this manner.

The atoms forming materials that have the right to be easily magnetized such as iron, steel, nickel, and also cobalt are arranged in tiny units, called domains. Every domain, although microscopic in size, includes millions that billions the atoms and also each domain acts like a tiny magnet. If a magnetic product is inserted in a solid magnetic field, the individual domains, i beg your pardon normally suggest in every directions, will slowly swing around into the direction of the field. They additionally take over bordering domains. When many of the domains are aligned to the field, the material becomes a magnet. (top)

Domains prior to magnetization

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Domains after magnetization

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What go a magnet do?

Magnets perform the complying with things:

Attract certain materials, such together iron, nickel, cobalt, certain steels and also other alloys.Exert one attractive or repulsive pressure on other magnets (opposite poles attract, like poles repel).Have an impact on electric conductors as soon as the magnet and conductor are relocating in relationship to every other.Have an effect on the path taken through electrically fee particles traveling in complimentary space.

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

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

How are magnets made?

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

Are there different types of magnets available?

There space three types of magnets: irreversible magnets, short-lived magnets, and also electromagnets.

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Temporary magnets behave as magnets while attached to or close come something that emits a magnetic field, yet lose this characteristic when the resource of the magnetic ar is removed.

There are numerous different varieties of permanent magnet materials, each through their own unique characteristics. Every material has actually a household of qualities that have properties slightly different from every other, though based on the very same composition. (top)

What are permanent magnets make of?

Modern permanent magnets room made of special alloys that have been uncovered through research to develop increasingly much better magnets. The most common families of long-term magnet materials today space made out of aluminum-nickel-cobalt (alnicos), strontium-iron (ferrites, additionally 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 family members are collectively known together the rare-earths). (top)

What space Rare planet Magnets?

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

What is a temporary magnet?

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

What space electromagnets?

Electromagnets are supplied when very strong magnets are required. Electromagnets are created by place a steel core (usually an steel alloy) within a coil of wire the carries an electric current. The electricity in the coil produces a magnetic field. The strength of the electromagnet counts on the strength of the electric current and also the variety of coils of wire. That is polarity depends on the direction of the present flow. While the current flows, the main point behaves favor a magnet, but as soon as the existing stops, the magnetic properties room lost. Electrical motors, televisions, maglev trains, telephones, computers, and many other modern-day devices usage electromagnets. (top)

What are eddy currents?

These are electric currents that are induced when a magnetic field moves in relationship to an electric conductor that has actually been put within reach of the magnetic field. In turn, this eddy currents produce a magnetic ar that action to prevent the relative activity of the original magnetic field and also electrical conductor. (top)

What do magnets cost?

Magnet materials have the right to vary considerably in cost from one come the other. Below is an almost right guide regarding magnet costs: