Author Topic: Preparation of powders for the SEM  (Read 4741 times)

emma_fisi

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Preparation of powders for the SEM
« on: January 25, 2017, 10:36:01 AM »
Hi All,

This is more of an SEM questions, rather than an EPMA question, but I'm hoping the hivemind can help out...

I have a user who wants to look at magnetic powder particles, and he is asking the best way to prepare these. We've had users sprinkle powders on carbon tape before, but I'm concerned about the magnetic aspect of this material. We don't know the grain size - that's one of the things he wants to determine in the SEM.

Has anybody got any tips and tricks for mounting up magnetic powders for imaging?

Many thanks,
Em

Probeman

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Re: Preparation of powders for the SEM
« Reply #1 on: January 25, 2017, 09:42:06 PM »
This is more of an SEM questions, rather than an EPMA question, but I'm hoping the hivemind can help out...

I have a user who wants to look at magnetic powder particles, and he is asking the best way to prepare these. We've had users sprinkle powders on carbon tape before, but I'm concerned about the magnetic aspect of this material. We don't know the grain size - that's one of the things he wants to determine in the SEM.

Has anybody got any tips and tricks for mounting up magnetic powders for imaging?

Hi Emma,
I don't have any mounting suggestions- are you wanting to image the particle surfaces?  In any case, you probably know that this type of sample could be very bad for a field immersion lens type instrument, where the sample sits within a strong magnetic field from the objective lens?
john
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emma_fisi

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Re: Preparation of powders for the SEM
« Reply #2 on: January 26, 2017, 01:48:41 PM »
Hi,

The user wants to image the particles (to get an idea of the range in particle sizes), and do EDS to see what elements are in their sample. They also want quantitative EDS, although we'll have to see how the particles look when they're mounted up.

I've heard from another user that the particles could be mounted in epoxy, which should hold them fast.... Our big concern is indeed the potentially messy consequences of a magnetic sample in a strong magnetic field....  I'll let you know how it goes :)

Cheers,
Em

Nick Bulloss

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Re: Preparation of powders for the SEM
« Reply #3 on: January 27, 2017, 12:26:26 PM »
Hi Emma,
I've mounted magnetic particles on carbon tape to be observed in a non-immersion lens SEM. I passed a magnet over the mounted sample to remove any poorly adhered particles.
Good luck,
Nick

emma_fisi

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Re: Preparation of powders for the SEM
« Reply #4 on: March 02, 2017, 07:06:00 AM »
Hi Nick,

That's a great idea! And a good use of the collection of kitten magnets on my filing cabinet ;)

Cheers,
Em