ASM Online Member Community

Hello everyone,

   I come to the forum to ask a question about sample preparation for Xray diffraction analysis. I have never had this analysis performed before. I have several solid metal samples (mainly Zinc/Aluminum) that I need to prepare in powder form for XRD. Does anyone have information or a contact that offers a sample preparation service?

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Brandon Lash
brandonl@wheeling-nipponsteel.com
(304) 527-4894
GM Quality Assurance and Customer Service
Wheeling Nippon Steel
Follansbee WV
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What exactly do you want to measure?   Here's a very good lab what can direct you.
https://www.lambdatechs.com/contact-lambda-technologies/


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Anthony Giammarise
consulting metallurgist
MOSTLY METALS
Erie PA
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Here is the lab where I send my samples to. James is very friendly and helpful person please contact him.

James Pineault P.Phys.

 Proto Mfg. Ltd.
6150 Morton Industrial Parkway

LaSalle, Ontario, Canada N9J 3W3
tel: 519-737-6330
fax: 519-737-1692
web: www.protoxrd.com
email: xrdlab@protoxrd.com

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Sanjay Kulkarni
Materials Engineer
MSSC
Troy, MI
248-840-1056
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Why do you need to obtain powder? Can't you directly cut a slice,  prepare it as a metallographic sample and obtain directly your XR spectrum. Crystals in the sample are randomly oriented, just as in a powder. Only if there is a compositional variation across the samples you need to crush only a specific portion.
Even in that case you do not need to have powder. I have analyzed by XRD nitrided samples with a constitution variation perpendicular to the heat-treated sample surface. By careful abrading a few microns at a time you have the constitution variation you are looking for. You may also assess if there is some specific crystal orientation on the samples surface.

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Donato Firrao FASM
Professor
Politecnico di Torino
TORINO
+393351494032
Italy
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Hello Brandon,

I agree with Donato, you don't need to make your samples into a powder. XRD people are often used to doing measurements on powder so that's whats often discussed or specified. It works perfectly fine with an XRD machine to measure on flat samples. In the past I've done this on metallographic samples that were also prepared for microstructure analysis. A high quality preparation suitable for SEM analysis should also be suitable for XRD evaluation as it won't produce distorted surface structure that you would then measure. 
As Donato says, you can also analyse layers in materials if you are careful with the equipment setup (the operator needs to to a bit more alignment work). This is done quite often with Thermal Spray coatings.

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Nicholas Nicholas Curry
Consultant
Thermal Spray Innovations
Bruck an der Großglocknerstraße
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Brandon -

It is more important to get the make/model of the XRD instrument, to
know their sample size requirements.  I am used to sample holders
35mm x 35mm x 3mm, which hold powder in a well/trough 15mm x
20mm x 1.5mm.  For that particular instrument, the  area  of 15mm x
20mm is the most important, as the depth could be between zero and 7mm.

For bulk samples, we were limited to 45mm(W) x 80mm(L) x 7mm (T).

Another instrument I know limits this to 30mm(W) x 50mm (L) x 3mm (T).

You really do not need to powderize your bulk sample.  Instead you could use
a plane and parallel plate.  It must be large enough to hold in the instrument
within the area of illumination.  However, realize that crystallographic texture
(preferential orientation of atomic planes) will alter relative peak heights, but
not their peak location (2theta or d).

kind regards,
- Jim

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James Quinn
Dir. of Laboratories
Stony Brook University
Stony Brook NY
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