So, found out the hard way that you can’t apply heat to neodymium magnets. Had 16 magnets to press into a print (tool holder). Thought since the soldering pen I use for inserting threaded nuts into prints works so well, I would use it for this too. And it did work well, but now all the magnets are not magnets any more. Yup, heat will demagnetize them. Part is useless, so had to trash it. Found out something new, but wish I had heard about this beforehand.
Commenter above you said 60*C.
Not saying you’re wrong but one of you is and I don’t think OP heated their magnets to 310*C+
I am pretty sure @Eheran is. I just paraphrased the linked Wikipedia article section for convenience. The video on how to print in magnets still worth watching, though.
It depends on the type/grade of magnet
https://e-magnetsuk.com/introduction-to-neodymium-magnets/temperature-ratings/
This should be higher up. OP clearly learned a lesson here but one larger lesson most everyone can learn is that neodymium magnets aren’t the only kind of magnets. Especially when high temperature performance is needed. Samarium Cobalt magnets are much better suited for high temperature and corrosive applications. Plus if I remember correctly they’ve been around longer.
Most neodymium loses it’s magnetism at 200-230C. Some Samarium Cobalt can retain their magnetic properties all the way up to 350C or higher grades up to 500C (1022F)
I nerded out on this a few years ago when I made a magnetic thermal blanket for my pellet smoker and experienced the same thing. Samarium Cobalt did the trick in my application.
I tend to solder at around 350C, so that’s entirely possible
This isn’t soldering though.
A soldering iron could be easily 310°C
Yes but it doesn’t need to be, and the soldering iron being 310 doesn’t mean the magnet is 310.
Fun fact - some soldering irons regulate their temperature using the curie point. There’s a disk of ferromagnetic material with a particular curie point in the tip. A magnet in the barrel of the soldering iron is attracted to the tip, and when it sticks to the tip, it switches the heating element on. When the disk hits its curie temperature it’s no longer magnetic, and the magnetic switch opens and shuts off the heating element (it’s on a weak spring). When the tip cools down enough it becomes magnetic again, and the magnet is pulled to it and turns on the heater. You can have different tips with different curie temperatures, so one soldering iron can do multiple temperatures with very cheap internal electronics (basically, just a switch).
ooh, that is a fun fact!