Looking for etched metal specimens (or possibly conc. nitric acid)

Cheshire Steve wrote:
<snip>


Yes I do. I'm thinking of buying one. I'm just researching the practicalities of it before I do.

Two reasons. Firstly for fun and to learn something. Secondly because I'm building a website about engineering design and therefore want a few pictures of the microstructures of common metals.
Best wishes,
Chris
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Chris,
I qualified as a metallurgist, but my work has taken me away from that now, but I have a hankering to get the capability back, and have slowly acquired a small furnace, microscope, and hardness tester (its wonderful what you can pick up on ebay). One thing I don't have is the arrangements for mounting and polishing specimens. You might get away without mounting, but you need to be able to get a good flat polish on the surface before etching. Normally successively finer water washed emery papers, then if I remember correctly we used 6micron and then 1 micron diamond paste on a rotating table a bit like a record deck, but with more grunt. Steel etching is a fairly quick affair with 5% nitric in ethanol (referred to as Nital), or maybe 10%. Different etchants could be used for other metals.
The core of metallurgy is understanding how heat treatment changes the microstructure of metals and hence modifies the properties, and understanding this means understanding the phase diagrams which show the solid state transformations, and then understanding how changing the cooling rate changes the microstructure. Much of the rest of metallurgy overlaps with other disciplines, for example fatigue failure, crack growth, overlap with mech eng; corrosion, plating, extraction, refining, overlap with chem eng; and ores and minerals overlaps with geology. For my money the best book I have seen on this 'core' aspect is Metallography of Phase Transformations by Chadwick, it really links the phase diagrams to the microstructure. I still have my copy as well as my notes from the lectures back in the 1970s - so if you want me to look some things up then drop me a line. I may even have some microstructure photos, though generally we drew them by hand - that way the significant features had to be appreciated by the brain cells. It reminds me of the quote that lecturing is the art of transferring information from the notes of the lecturer to the notes of the student without passing through the minds of either - it is of course not true!
Best of luck.
Steve
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I have a metallurgist's "belt sander" - it has a much superior belt-tracking arrangement than the usual hardware-store version, facilities for keeping the sample and belt wet, and a wash sump.
It's a bit bulky, though - I'd swap it for a more ordinary linisher as long as it had reasonable belt control.
-adrian
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Adrian Godwin wrote:

Thanks for the offer. I don't have a linisher around to swap for it, though.
Just out of interest, what make and model is it? I might look out for a similar one.
Best wishes,
Chris
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It's a Metaserv C1850A (read off the plate - I have no idea if that's good or bad!). Here's a picture :
http://www.flickr.com/photos/23312780@N04/2228532703 /
I was planning to strip it down and use the mechanism to make something more suited to my needs, but it seems a shame if someone needs it as-is. I'm sure we could come to some arrangement if you or Steve want it.
I notice there's also some sort of diamond grinder on ebay - maybe this would do for finishing ? Needs a bit of work ..
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item &0205896898
-adrian
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It's a Metaserv C1850A (read off the plate - I have no idea if that's good or bad!). Here's a picture :
http://www.flickr.com/photos/23312780@N04/2228532703 /
I was planning to strip it down and use the mechanism to make something more suited to my needs, but it seems a shame if someone needs it as-is. I'm sure we could come to some arrangement if you or Steve want it.
I notice there's also some sort of diamond grinder on ebay - maybe this would do for finishing ? Needs a bit of work ..
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item &0205896898
-adrian
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Cheshire Steve wrote:
<snip>

Just out of interest, what microscope do you have? I've been looking at a Watson "Standard Metallurgical".

Thanks very much for the reference and the offer. Sorry I missed the reference on Sunday. I read the posts here rather hurriedly.
Best wishes,
Chris
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Its a Vickers M12a - I don't remember how much I paid for it, but very happy. However I waited quite a while for a metallurgical one that was at a good price and within driving range - this was in Liverpool.
The top photomicroscopes I used were Zeiss - but you are talking money for one of those.
Best Regards Steve
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Cheshire Steve wrote:
<snip>

In the end I decided to buy the Watson "Standard Metallurgical" microscope. It should be with me in a week or so. If I get any great pictures, I'll post them for everyone to see!
Best wishes,
Chris
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Cheshire Steve wrote:
<snip>

Yes Steve, I'd be interested in your book recommendation.
I already have "Practical Microscopical Metallography" by Richard Greaves and Harold Wrighton, if that's the one you're thinking of.
Best wishes,
Chris
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See my earlier note for the reference.
Please contact me offline, if I can help I will. You know they say metallurgy is the second oldest profession !
Steve
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Cheshire Steve wrote:

I can never remember what the oldest is supposed to be. Is it farming or prostitution? :-)
Chris
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