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Hi Ritchie,
And just to quickly add to all the good advice you have been given, I'd like to say Light Elements.
If I was going to do light element analysis, I would always choose WDS over EDS (even the new super fast SDD EDS systems).
I like the sensitivity and energy resolution of WDS detectors for x-rays below 1 keV, and in particular below 0.5 keV.
For non-geological applications I've been asked to look at beryllium copper, and cast irons full of carbides and borides, plus there is also ceramic nitrides used as refractory materials and coatings for machine cutters.
Cheers,
Ron
Ron Rasch
The University of Queensland
Brisbane, Australia
________________________________________
From: JEOL-Focused Probe Users List [[log in to unmask]] on behalf of Julien Allaz [[log in to unmask]]
Sent: Thursday, 21 June 2012 8:07 AM
To: [log in to unmask]
Subject: Re: [PROBEUSERS] AW: [PROBEUSERS] Case for a new EPMA
JEOL Probe Users Listserver
Moderator: Ellery Frahm, [log in to unmask],
Electron Microprobe Lab, University of Minnesota
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*
Sorry, I meant a beam resolution of ca. 0.7 MICRO-meter (not nm...) with
a LaB6....
J.
On 6/20/12 1:06 AM, Gerald Schmidt wrote:
> JEOL Probe Users Listserver
>
> Moderator: Ellery Frahm, [log in to unmask],
> Electron Microprobe Lab, University of Minnesota
>
> Post a message: send your message to [log in to unmask]
>
> Unsubscribe: send "SIGNOFF PROBEUSERS" to [log in to unmask]
>
> On-line help and FAQ: http://probelab.geo.umn.edu/listserver.html
>
>
>
> *
>
> Ritchie,
>
> what an exciting prospect! I hope your case will be successful.
>
> I work at an institute that's mainly focused on materials research. We
> are using a medium-old SEM (W cathode) and a medium-new EPMA (JXA-8100).
> Our researchers as well as our industrial partners appreciate both
> methods for their respective strengths.
>
> Would your department cooperate with the the School of Engineering, i.e.
> would your new microprobe be available to them? If so, I think they
> should be quite supportive!
>
> According to the website of the Research Centre for Surface and
> Materials Science (RCSMS), their SEM equipment is new and provides
> high-performance electron imaging thanks to their Field Emission (FE)
> sources. A microprobe could and should not compete with that. However,
> even high-performance FE SEMs can not provide better spectral EDS
> resolution than the WDS of a microprobe. For example, how do they
> resolve the problem of line overlaps, such as Mo and S?
> Especially in our research field of high temperature materials, we often
> look at alloys containing Mo, and aggressive environments containing S,
> and we want to be able to tell what happens on and below the metal
> surface when those alloys are exposed to high temperatures in aggressive
> environments. You could think of other examples too, and I'm sure the
> RCSMS would love to have a WDS solution at hand!
>
> Another strength of the EPMA clearly is element mapping. Even the
> coolest FE SEM will produce rather sad looking maps (some examples
> provided on the RCSMS website). I bet if you show a comparison of EDS /
> WDS maps this will convince some people! Especially industrial
> researchers love our colourful WDS maps.
>
> Finally, when it comes to precise quantification of alloying elements in
> special steels or Nickel-base alloys, we know we cannot rely on EDS.
> Even just the word "standardless" should ring some alarm bells!
> Of course it will be challenging to make this point without sounding too
> critical about the work that's been done at the RCSMS so far ;-)
>
> Good luck!
> Gerald
>
> ------------------------
> Dr. Gerald Schmidt
> DECHEMA-Forschungsinstitut
> High Temperature Materials
> Theodor-Heuss-Allee 25
> 60486 Frankfurt am Main
> Germany
>
> Tel: +49-69-7564-355
> Fax: +49-69-7564-388
> E-Mail: [log in to unmask]
> http://www.dechema-dfi.de
>
> DECHEMA-Forschungsinstitut • Stiftung bürgerlichen Rechts
> Vorstand: Prof. Dr.-Ing. Michael Schütze (Vors.), Priv.-Doz. Dr. Jens
> Schrader
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> Anerkannt durch das Regierungspräsidium Darmstadt unter Az.
> I13-25d04/11-(12)-720
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>
>
> -----Ursprüngliche Nachricht-----
> Von: JEOL-Focused Probe Users List [mailto:[log in to unmask]] Im
> Auftrag von Ritchie Sims
> Gesendet: Donnerstag, 14. Juni 2012 09:12
> An: [log in to unmask]
> Betreff: [PROBEUSERS] Case for a new EPMA
>
>
> Hi
>
> For the past ten years we have been using a JXA-840A with EDS for
> quantitative geological
> work, it's been OK, for analytes > about 0.2%, but there is a chance now
> to make a case for
> a brand-new 'proper' EPMA.
>
> The complication is that we have to find as many potential users, from
> within and without the
> University, to support us.
>
> In the School of Engineering there are a couple of SemS, with close ties
> to local industry, and
> because their standardless analytical packages give element
> concentrations to two decimal
> places, they and their users accept that their results are quantitative
> (!).
>
> They are likely to oppose our getting a new EPMA as it would probably
> reduce their revenue
> stream.
>
> I know virtually nothing of probe applications outside Geology.
>
> I would really appreciate hearing of EPMA projects and applications in
> non-geological fields
> to help me prepare a case. It would be great to list those for which an
> EPMA beats an SEM
> hands-down.
>
> cheers
>
> Ritchie
>
> --
> Ritchie Sims Ph D Phone : 64 9 3737599 ext
> 87713
> Microanalyst Fax : 64 9
> 3737435
> Department of Geology email :
> [log in to unmask]
> The University of Auckland
> Private Bag 92019
> Auckland
> New Zealand
--
**********************************************
Dr. Julien Allaz
Research Associate
Electron microprobe manager
University of Colorado Boulder
Geological Sciences
UCB 399
2200 Colorado Ave.
Boulder, CO 80309-0399
USA
Have a look at my Home Page!
=> http://geoloweb.ch/ <=
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