Using Magnets

I have a product where I have magnets in some parts of it. When I heated the magnets up, they lost their strength. This finding was confirmed this morning when a friend warned me of the same issue if washing magnets in a hot diswasher. The magnets I heated up when first making my prototype were exposed in an oven @ 270 degrees.

If I ensure that these magnets are not exposed, but centered in a blob of plastic, will they be protected enough to be washed in a sink of hot water without losing strength?

Thanks

Great question. See what you can discover when you start to experiment and prototype.

Short answer, washing in a sink of hot water should be OK. Keep away from ovens. Here is a more in depth answer.

I did a bit of research and found this from: http://www.rare-earth-magnets.com/magnet_university/magnets_FAQ.htm

"Will my magnets demagnetize if I heat them?

Yes, if you heat them beyond 170 degrees Fahrenheit (80 degrees Celsius) the magnets will quickly loose their magnetic properties. Sustaining these temperatures for a length of time or heating the magnet significantly higher than this will permanently demagnetize it. Other types of magnets such as Samarium-Cobalt have higher heat resistance. There are also other types of Nd-Fe-B magnets that are not as susceptible to heat induced flux degradation."

I have read that companies do insert mold magnets in an injection molding process. It would depend on what type of plastic you are using and the type of magnet.

Great!

Thanks so much Stephen!

Tania, years ago I had the same problem with magnets....I new very little about magnets, guess I missed that part in school.. I ended up talking to some proffessors at the University Of Kentucky to get educated on the magnets.....I needed small magnets that had a lot of power. The University got me tied up with a company "Crumax" I was able to get more educated from them also. Crumax sells all different kinds of magnets, check the out.

One thing I didnt know was anyone that has a heart pacemaker should stay away from any type of magnets.

I'll be reading all about magnets today. These little things are a lot more interesting than I first thought!

Thanks Gizmo!