Ceramic Magnets and their durability in temperature fluctuations

[bluerayz]

I work in the Aggregate industry and we use ceramic magnets to pull ferrous materials out of the feed of Aggregate materials passing by on a conveyor belt.
So i have a basic knowledge about how they work, but my technical knowledge about magents is extremely lacking.

Wondering if anyone would have any theories as to why a ceramic permanent magnet would lose its strength working in a place with extremely cold temparatures? I.E. -40° C.
I know that permanent magnets become stronger when they are put in extremely cold temps, but I'm wondering if going from -40 to +20 every 24 hours for months in a row might gradually decrease the strength over time??

Any thoughts would be helpful. Thanx in advance.

 

[nasu]

What kind of ceramic? Is it a ferrite?

 

[bluerayz]

It is Ferrite.

 

[nasu]

The values of the coercive field of some ferrites may decrease significantly at low temperature. This will make the magnet more sensitive to weak external fields, which may demagnetize it or reduce its magnetization.

 

[sardar]

I can provide some insights about ceramic magnets and their durability in temperature fluctuations. Ceramic magnets are a type of permanent magnet made from a combination of iron oxide and strontium carbonate. They are known for their high resistance to corrosion and their ability to maintain their magnetic properties at high temperatures, making them suitable for use in industrial applications such as the one you have described in the aggregate industry.

However, like any other material, ceramic magnets can also be affected by extreme temperature changes. When a magnet is exposed to extremely cold temperatures, its magnetic domains align in a more ordered manner, making the magnet stronger. On the other hand, when the temperature increases, the magnetic domains become more disordered, resulting in a weaker magnet.

In your case, the constant temperature fluctuations from -40°C to +20°C every 24 hours for months can indeed have an impact on the strength of the ceramic magnet. This is because the repeated changes in temperature can cause the magnet to expand and contract, leading to microcracks and changes in the alignment of the magnetic domains. Over time, these factors can contribute to a gradual decrease in the strength of the magnet.

To mitigate this issue, it is important to choose a ceramic magnet that is specifically designed to withstand such extreme temperature fluctuations. Additionally, proper maintenance and handling of the magnets can also help prolong their durability. I hope this information helps and I would be happy to discuss further if you have any other questions.