Neodym magnet information

Neodym magnet information

Neodymmagneter er de stærkeste permanente magneter, der er kommercielt tilgængelige, hvor som helst i verden. De giver uovertrufne niveauer af magnetisme og modstand mod afmagnetisering sammenlignet med ferrit, alnico og endda samarium-kobolt magneter.

NEODYMIUM MAGNETERS HISTORIE

Neodymmagneter blev først udviklet i 1982 af General Motors og Sumitomo Special Metals efter formuleringen af ​​legeringen NdFeB, som er lavet af neodym samt jern og bor. Neodymmagneter blev først produceret som svar på den høje pris på samarium-koboltmagneter, giver behov for at identificere en økonomisk, højtydende magnet. Selvom det er formuleret i fællesskab, General Motors og Sumitomo Special Metals fulgte forskellige fremstillingsprocesser, hvor General Motors valgte at producere neodymmagneter i pulverform, mens Sumitomo fulgte sintringsfremstillingsprocessen, the same process used to manufacture our range of neodymium magnets.

Sjælden Jord

Neodymium magnets are also described as rare-earth magnets, because neodymium is part of the rare-earth family of elements. The term rare-earth does not mean they are scarce, neodymium is abundant in the Earth’s crust – in fact it is more common than some precious metals such as gold – the term derives from their geochemical properties, rare-earth elements are typically dispersed and not often found concentrated in economically exploitable deposits.

Neodymium is not the only element used to make neodymium magnets; neodymium is combined with boron and iron and sometimes other elements too to make super-strength magnets, just like those supplied by umagnets.com.

Neodymium Magnet Grades

It all starts with the letter ‘N’, all the names of neodymium magnets begin with ‘N’ for neodymium. The number that follows is a little more technical as this represents the maximum energy product of the magnet in ‘Mega-Gauss Oersteds’ (Mgoe). This is the primary indicator of a magnets ‘strength’. Simply, the higher the maximum energy product value, the greater the magnetic field the magnet will generate in a particular application.
The grades generally available to buy, range from N30 to N52 as lower grades are generally no longer manufactured.

Neodym magnet – Platings/Coatings

Neodymium magnets are very hard, but very brittle. Plus, as neodymium magnets also contain iron it means they are prone to corrosion if they aren’t coated. They are so prone to corrosion that even the moisture in the atmosphere can cause an uncoated neodymium magnet to corrode over time. If a magnet corrodes it will weaken and crumble

That’s why, at umagnets.com we supply all our magnets already triple-coated (unless specifically requested otherwise). The typical coating for a neodymium magnet is a layer of nickel followed by a layer of copper and then nickel again. However there are many different coatings used with neodymium magnets including gold, rubber and Polytetrafluoroethylene (PTFE). The coating applied to a raw neodymium magnet depends on the application it will be used for, potential coatings include:

• Nikkel-kobber-nikkel (Ni-cu-ni)
• Gummi
• Nikkel (I)
• Epoxy
• Zink (Zn)
• Guld (Au)
• Tin (Sn)
• Titanium (Ti)
• Titanium Nitride (TiN)
• Parylene C
• Everlube
• Chrome
• Polytetrafluoroethylene (PTFE)
• Nikkel-kobber-nikkel, plus Rubber
• Zink, plus Rubber
• Nikkel-kobber-nikkel, plus Parylene
• Nikkel-kobber-nikkel, plus PTFE
• Tin, plus Parylene
• Zinc chromate
• Phosphate passivation

During manufacture, all our magnets are thoroughly dried to prevent moisture being captured underneath the coating during the coating and plating process.

How does temperature affect neodymium magnets?

In the application of neodymium magnets, it is critical to understand the maximum operating temperature of each grade of magnet. Neodymium magnets operate best at lower temperatures, they even get stronger as the temperature gets colder, to a point of approximately -130°C. Imidlertid, some grades of neodymium magnets can also be exposed to very high temperatures before their properties begin to change and they lose their magnetism, either temporarily or permanently.

Uses of Neodymium Magnets

Neodymium magnets are the strongest magnets in the world. På grund af deres styrke, even tiny magnets can be effective. Dette gør dem også utroligt alsidige; som hver af os går om vores moderne liv, vi er aldrig langt fra en neodymmagnet, du har sandsynligvis en i lommen lige nu, eller hvis du læser denne artikel på smartphone, du har måske endda en i hånden!