Will a magnet lift a very thin coated sheet of nickel?

AI Thread Summary
A small magnet may struggle to lift a thin nickel-coated sheet due to the reduced thickness of the ferromagnetic layer. The sample consists of a 10mm x 10mm copper base, with nickel and gold coatings, where the nickel is only 0.005mm thick. Compared to a previous sample with thicker nickel, the thinner layer significantly decreases the number of magnetic domains, potentially reducing the magnet's holding power. However, the overall weight of the sample is also lower, which could balance the reduced magnetic strength. Testing with the existing sample may provide practical insights into the magnet's effectiveness.
Stuey
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Hi, I am trying to work out if a small magnet can be used to hold a thin sample that I have. The sample is flat and about 10mm x 10mm in size. The sample is a layer of copper, with nickel plated on that. There is then a gold coating on the nickel. The copper is 0.05mm thick, the nickel 0.005mm thick and the gold 0.005mm thick. The magnet would be in contact with the gold layer.

I had a previous sample that the magnet could lift, but this had x10 thicker nickel (0.05mm thick). I am wondering if reducing the thickness of the ferromagnetic layer will reduce ability of magnet to hold the sample against gravity ?

Thanks for the help
 
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It may well do ... why not try it and see?
 
I was interested to know if the problem has a simple analytical solution (and I won't have the parts for several weeks)
 
I see ... the problem does not have a simple analytical solution.
You could back-of-envelope it ... the thinner metal would have 1/10th the magnetic domains so pretend the sticking power is 1/10th as strong but the weight is also smaller.
(You culd also see how much extra weight you can hold using the existing sample.)

These are milligram quantities though.
Unless your magnet is very puny, it should be like picking up iron filings.
 
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