unfortunately this is not a "trivial and simple method". It is trivial and simple to get numbers out of a software.. it is extremely difficult to be sure those number has some physical meaning. The outcomes of the recent Accuracy in Powder Dffraction conference (held every 10 years) are really those: accuracy is an issue.

For surethe Reitveld method is the one that can give the highest accuracy if used properly and if you know what you are doing (never ever use it as a black box)

It is very trivial and simple method. Please see the attached file

http://epswww.unm.edu/xrd/xrdclass/09-quant-intro.pdf

unfortunately this is not a "trivial and simple method". It is trivial and simple to get numbers out of a software.. it is extremely difficult to be sure those number has some physical meaning. The outcomes of the recent Accuracy in Powder Dffraction conference (held every 10 years) are really those: accuracy is an issue.

For surethe Reitveld method is the one that can give the highest accuracy if used properly and if you know what you are doing (never ever use it as a black box)

As a first approximation to quantify the phase composition you can use the program "PowderCell 2.4". It's pretty simple, and free in internet

I would suggest if you know what is your second phase : add and mix well a known amount of it, like 1% to your sample and make a new diffraction pattern -> check the result, detected or not ? how much more ? after you'll do the math :-)

Gerard, spiking can be quite dangerous if you don't do it properly! Plus in this case the measurement is on a sintered ceramic!

Rietveld refinement is the first and wise choice to identify the secondary phases, there are a variety of softwares available for Rietveld refinement such as Topas, GSAS, Fullprof.

Suresh - I expect you meant that Rietveld refinement is useful to QUANTIFY second phases, which I agree with. To IDENTIFY second phases you need search-match software and a database, not GSAS or FullProf.

Khaliq Jibran! (A famous name in literature is Khalil Jibran/Gibran)

Q. "How can we quantify the two phases present?"

A. Besides all of the above answers would by creating a set of "known standards" to compare with and develop a calibration chart. This would be the most reliable & precise practical method in my opinion for routine XRD examination of your sintered composites.

If this is a one time R&D phase ID then your sample preparation and mounting will be critical for precise quantification. You would have to eliminate the contributions from several factors including and not limited to:

1. Instrumental aberrations.

2. Specimen morphology and homogeneity.

3. Preferred orientation.

4. etc.

BTW please post a photo of your sample and your sample mount. What is the approximate chemical composition of your material? Post some of your XRD data when convenient.

It may be prudent to consider the transmission geometry and scan the sample while acquiring and analyzing the "ever present" 2D XRD signal.

Please take advantage of this recent webinar presented by the good folks at Panalytical regarding "X-ray Diffraction Techniques in Transmission Geometry":

http://www.linkedin.com/groupItem?view=&gid=2683600&type=member&item=257395175&qid=8ecf52e7-f76e-430e-aff1-e64341a074d2&trk=group_most_recent_rich-0-b-ttl&goback=%2Egmr_2683600

[email protected]

Ravi, unfortunately nobody in he XRD community would agree with you that a calibration chart is the most reliable method. With calibration curves you can have (on average) an error in the quantification that can be of the order of 20%.. with the Rietveld method you can go down to 5%. This does not mean you can't do better: if your specimen and data are appropriate (not always the case) and if you know what you are doing (experience) the figures can be better

I get excited when I get a "Green" click from you Matt! 5-20% is "operator error" (The No Clue Factor), in my humble opinion. It certainly is not a limitation of the technique. I would certainly take advantage of the Rietveld technique both in transmission and reflection modes to develop the calibration chart. It is not so much that the community doesn't want it, as much as the Manufactures have not enough "expertise" in the application end to sell it. Perfect example is the rare use of 2D diffractorams versus the ubiquitous 1D version. I've never heard of anyone considering the Rietveld or the Warren-Averbach analyses of 2D diffraction patterns. Most end up reducing the 2D pattern to 1D and then travelling back in time to the "Neolithic Past" most times in a horse cart named 0D point counter (scintillation counter). It appears as if time has stood still in the field of XRD since about 1988 when I quit to go get a real job in Real Estate and the Financial World. That is scandalous!

Do rietveld analysis. Before that you should find out peak profile of XRD machine, appropriate scan speed so that you get good fit.

Yes Dr. Edward Payzant, to identify secondary phases softwares such as Match is necessary, to quantify secondary phases Rietveld can do a great job.

Rietveld refinement is the best way to go. Try to grind your probe fine enough (if the second phase allows it!) and measure carefully the pattern.

Alex! Do you mean grind the sample in to powder? That would certainly introduce additional defect into the "crystallites" if crystalline. In other materials this may manifest itself in other ways in the diffractogram.

For an invariant sample with an invariant sampling surface plane and invariant instrument error, one may be able to use the Rietveld refinement at each probe point to develop a 2D map for the sample. Sort of like a SEM/TEM without the vacuum.

Ravi! Mapping in 2D with a conventional source is a loss of time for obvious reasons.

Ravi, you want to use a block in the diffractometer and you hope to have the sample random enough not to have preferential orientation? Well I will not bet on it...

The question here is "quantification" and not "microstructure analysis". Grinding powder is a classical method to obtain homogenous samples, and this is the only way to obtain an homogeneous sample...

Alex!

1. I agree, the conventional 0D method would be "time prohibitive" for 2D XRD analyses including "pole figures".

2. " you want to use a block in the diffractometer and you hope to have the sample random enough not to have preferential orientation?" I don't follow this.

3. "Quantitative Microstructural Analysis" = "quantification of crystallography". This is my presently informed opinion. Please clarify your contention.

4. "Grinding powder is a classical method to obtain homogenous samples". That's right Alex! It is the classic "smudge factor" applied in most XRD analyses for the past century and is highly contentious. It is however a great way to determine an average crushed "XRD parameter" for the "destroyed" sample. You could subsequently argue about the best numerical method to deconvolute the micro lattice strain and "coherent diffracting domain size" from the convoluted (smudged) mess. Additionally, as you have stated earlier, a futile exercise in time to accomplish in 2D. We are of course discounting the total blindness to any preferred orientation with the conventional method.

This is 2013 and experts in XRD ought to realize that the "loss of time" is not as big as the "loss of 2D data" by deliberately neglecting it. Bragg, Scherrer, Ewald, Von Laue, etc. would be highly uncomfortable wherever they would be with such deliberate discounting of 2D XRD data. With the real time 2D XRD tools available today the only excuse for not using them is "temporary ignorance". You certainly would not be able to use the omnipotent Scherrer equation to resolve "size effect" with conventional diffractometry (with 0D detector) in the presence of preferred orientation.

I see Mateo's point when it comes to community thought process. Old habits are hard to break. However, it is amazing what is on the other side of the curtain once you are able to "come out of the conventional box". I liberated myself from conventional 0D detectors nearly 3 decades ago and have never looked back in remorse. You ought to try it. Just use stupid old dental film & you'll see my PoV (point of view). Of course, if you still have film where you are. Polaroid X-ray photographic film is nearly extinct today unless you move to Timbuktu! Lol!

Ravi,

1. the question is "quantification", that is how much do I have of A in a mixture of A and B. Microstructural analysis is the question about the size and shape of A 'coherently diffracting voxel'. It is comparing apples and pears.

2. we are again interested into the quantification. You don´t even need an IRF function to perform quantification...

3. You have to crush your sample. If you measure a monolith of your product, you may not have a representative sample. This can happen if the penetration volume of your X-Ray is too small. The results then are bullshit.

4. you don´t want to get microstructural data, so who cares about this problem? There is no smuggle part...

5. I do not hold much of 2D data except if you are using the preferential orientation in a clever manner, which is not a trivial sport....

Simple questions:

1. How many XRD users have actually verified the exact "sampling size" by monitoring the beam impinging on the sample?

I accomplished this by placing a Polaroid dental film where my sample should have been in the past. These days I record real time videos (5-60fps, up to 3000 frames per second possible). "Incident Beam Profile" for a Panalytical MRD machine: http://www.flickr.com/photos/85210325@N04/9248173496/

2. How many XRD users think the "Incident Beam"(Io) is relevant enough to record?

I've made it a practice to do so right before & after every experiment. This is critical for 2D analyses since there is a 2D shape factor for the incident beam.

Alex! "bullshit" (BS) is an euphemism for "temporary ignorance". Don't forget even BS has its use. In India they use it as an "ecologically sound" fuel source.

If you are open-minded then I suggest you study the latest webinar by Panalytical clearly expelling the BS factor. If not you would have to remain smug in your present state if information. As "a man convinced against his will is of the same opinion still" (from a classic book - As A Man Thinketh)

http://www.linkedin.com/groupItem?view=&gid=2683600&type=member&item=257639037&qid=1a7fcec9-84e5-473b-a10b-968ae5f6cfdf&trk=group_most_recent_rich-0-b-ttl&goback=%2Egde_2683600_member_231584534%2Egmr_2683600%2Egde_2683600_member_257395175%2Eanp_2683600_1373743237815_*2%2Egmr_2683600%2Egde_2683600_member_257395175%2Egmr_2683600

Just curious, have you any experience with 2D detectors at all? What type?

I'm not sure how you came up with the definition of microstructural analyses not needing to be quantitative. You are making it up as you go along, I suppose.

"There is no smuggle part..." what's that Alex? Do you mean "smudge" or "average" or "convolution"?

"you don´t want to get microstructural data, so who cares about this problem?" Since you don't care the 2D data is irrelevant to you and your definition of microstructural analysis is not precise. The word "analysis" is quantitative. If you are practicing analyses without quantification then you would be guilty of producing BS aerated with a little bovine flatulence as well. That is the frolic part of this experience. Lol!

Here is the BS factor: "You have to crush your sample. If you measure a monolith of your product, you may not have a representative sample". Not at all, you would be measuring "crushed" monolith of what was your product. You probably don't care because you do not have the resolution or the expertise (software/hardware) to handle it.

"I do not hold much of 2D data" because you don't know what to do with it. Your equipment provider has no clue how to tackle it. I bet you don't even have a way to store the data in a compact video format. If you do, then send me some .AVI video files of your 2D data. I'll help you analyze it and post the results for the benefit of all those that are really interested in breaking out of old habits.

This is where "the rubber meets the road". This is all irrelevant "if you don't care".

[email protected]

Data talks BS walks! I'd like to remain academic in the verbiage if possible. It would make more intellectual sense and reduce the "noise" while keeping our message (signal) clear. Robust, I don't mind.

NDE Real Time Insitu Bragg XRD Microscopy of a Sintered Composite Product with 3D Nano structural morphology of crystalline and other constituents:

Step 1: Identify sampling depth, as astutely pointed out by Alex, for the composite sample.

Step 2: Determine the sampling wafer thickness suitable for XRD in both reflection & transmission geometries. The wafer would minimize the surface damage layer due to slicing (only for transmission optics) compared with "crushing"/"powdering" with a mortar & pestle. I shudder to think of those poor little crystallites.

Step 3: Choose wave length based on penetration depth desired.

Step 4: Use tools and techniques described in the following videos to image Nano structure in 3D.

Step 5: Choose beam size and conditioning.

Step 6. Collect real time data! Simple. Installs in 30 minutes on most existing diffractometers including Panalytical, Bruker, Bede, Phillips,GE, Diano, or any other "home made" version of a diffractometer you are struggling along with. Requires a 110V power supply with in the enclosure and a 20 ft. USB cable leading out safely.

1. YouTube Video Play List: http://www.youtube.com/watch?v=IU0m4yI7D-k&list=PL7032E2DAF1F3941F

2. Panalytical Free Webinar: http://www.linkedin.com/groupItem?view=&gid=2683600&type=member&item=257639037&qid=1a7fcec9-84e5-473b-a10b-968ae5f6cfdf&trk=group_most_recent_rich-0-b-ttl&goback=%2Egde_2683600_member_231584534%2Egmr_2683600%2Egde_2683600_member_257395175%2Eanp_2683600_1373743237815_*2%2Egmr_2683600%2Egde_2683600_member_257395175%2Egmr_2683600

Anyone with access to .AVI format (and many other formats) video data from your XRD data (only if "open research" unless you want to pay for confidential/proprietary status data), may send for analyses. Let us show you!

[email protected]

Alex! I'm hoping you'll have some time to sit back (much better than "flying by the seat of your pants") at the widest screen TV monitor you can find and then enjoy the music (at least). Equip yourself for the trip with the right beverages. This is my challenge to you for all the bloviating you've put us through. Lol!

I certainly value the learned opinion of one such as you. Your critical evaluation of this awesome technology is my objective.

I'm confident that samples such as Khaliq's would be ideally amenable to quantitative microscopic analysis with either a micro focus source and lateral (2D) scanning or with a 2D coherent source scanned (1D) over the wafer. You just have to understand the value of the 2D data to appreciate. To top it all it is real time. It took me nearly an hour to collect a standard 1D diffractogram using a conventional 0D device. BTW this "quantitative value" gave me no indication of the local spatial changes in the Nano structure including grain/sub-grain boundaries. We are discussing well beyond the Rietveld process and are delving deep in to the Nano structure spatially.

It would be awesome to see some micrographs of the typical sample that Khaliq is interested in. This would give us a better idea of the constituent size & distribution in the sample. For only then can we make intelligent suggestions of optics and resolution needed.

You are trying to sell us 2D powder diffraction as a new potent method. It would work if

(a) your resolution in space is definitively poor,

(b) you need to deconvolute your data because your beam is not a single point-like source,

(c) you have to integrate your data at a given time in 1D datasets.

All the rest is definitively not new and can be done much better at synchrotrons

And now some points about me and some comments

(a) thank you I have quite a good idea of 2D detectors as they are very useful and can bring a lot of information, especially for coherent diffraction imaging. I usually prefer for my PXRD data 1D detector because then I can get a good error estimator.

(b) for sintered samples the grain size is usually very large. It means that the experimental broadening is smaller than the instrumental broadening so you cannot determine grain size. If you grind your sample you will not destroy your grains.

(c) I can do QUANTITATIVE phase composition analysis and QUANTITATIVE microstructural analysis.

(d) what is your definition of microstructure?

(e) you need to deconvolute your data because of the smearing caused by your beam geometry. Any idea of how much error you are introducing?

(f) what is the definition of 3D data measurements?

and the better for the end:

"I certainly value the learned opinion of one such as you. Your critical evaluation of this awesome technology is my objective."

"I'm not sure how you came up with the definition of microstructural analyses not needing to be quantitative. You are making it up as you go along, I suppose."

Who is not serious from us both?!!! Why is your so "awesome" technology still not available for the rest of the World?

To quote Lyndon B. Johnson "I may not know much, but I do know the difference between chicken shit and chicken salad. "

Alex! You seem to be highly knowledgeable about feces (chicken & bull) besides XRD. However, I would recommend some enhancements to your vocabulary so that your words are more palatable to all of us.

"You are trying to sell us 2D powder diffraction as a new potent method" - Promote perhaps, sell no. This is technology that you certainly wouldn't appreciate if you think it is powder diffraction. You couldn't afford it anyway & I can't export it to you yet. BTW I'm not sure what you are "selling" besides skepticism & brashness. Investigate!

Now, since you have no questions about the beam conditioning in my case I presume that you "don't care" about that either.

Just so you understand all the data for single crystal work was obtained with a standard

Back to the original question:

Q. Is there any way of quantifying the second phase by XRD in sintered ceramics?

A. Yes! Matt, Volker & others have answered in detail.

Q. How can we quantify the two phases present?

A. Through the use of Rietveld and other similar powder diffraction analysis tools. The use of "known standards" to compare would be highly advantageous. An abundance of care is required for using these techniques. Choice of various parameters for the software analyses is critical and highly subjective. Avoid using the various XRD software tools in a "black box" mode.

Once the sample is standardized then it may be feasible to use the powder method to map the microstructure quantitatively in 2D. There is no need to "grind & crush" a sintered sample for XRD powder diffraction analysis. Put it in as-is on to the diffractometer. Just make sure you have at least a flat surface on the sample. This is most likely so for the sintered sample as it may have been compressed under stress prior to sintering. Some surface grinding (limited surface damage) may be more acceptable than wholesale "crushing & grinding".

It would be OK to "crush & grind" to get a rough handle on the diffraction pattern, but it would be wise to mount the sample "uncrushed" directly on to the sample mount to confirm the "as-is" sample diffraction pattern. Certainly compare the two. Let us know if they are the same or that "crushing & grinding" alters the diffractogram. In addition, rotate the sample about its surface normal and get XRD pattern to eliminate the presence of preferred orientation in the sample.

Rocking curve recording require a specific setup.... Not a 2D detector...

So, if your technique has no resonance it is because we are all stupid and stubborn? I think this may be an issue. The further the discussion goes the funnier it gets...

"Rocking curve recording require a specific setup.... Not a 2D detector..." QED! You are clueless! Not only that Alex, you have no grasp of the subject of XRD Rocking Curve analysis just yet. All you seem to be interested in is irreverent & gratuitous self gratification. How did you manage such a high RG score? 26.35 · 99.72 ( You are highly intelligent. That I can sense even from this distance. Your publications are your credentials and I applauded you for your achievements! I'd love to study them. Email them to me if you still feel gracious enough. I'll request what I can, through RG as well. I promise to get through to your intellect sooner or later through hard data and experimental observations & evidence.)

Send me your X-ray rocking curve data "hot shot". You don't have any, I bet. Just pontificating aimlessly about a subject you have no clue about would qualify as temporarily "stupid", I suppose. Dismissing years of research without even reviewing the myriad of publications would also qualify as temporarily "close minded" besides "stupid". The good news is, it is not a permanent affliction. At least you've elevated yourself out of the feces for now.

"So, if your technique has no resonance it is because we are all stupid and stubborn?" Not really! I'd classify it as "temporary ignorance". Don't include "we" just "I" above. Don't forget when the earth was "flat" only a couple of hundred years ago there was no "resonance" for the concept of a "round" earth and that the earth was not the "center" of our universe.

OK! Alex! I stepped in to some serious dog dudu!

"Zone-doubled Fresnel zone plates for high-resolution hard X-ray full-field transmission microscopy." Fascinating topic! Please send me your publication in PDF format when convenient. I'll try on my own to dig it up as well.

[email protected]

What is the beam size (sampling VOXEL size)? Not sure how to ask this question as I am in extremely unfamiliar territory. Now I feel "stupid".

Here is the 2D version of rocking curve analysis from our friends at the EU Synchrotron facility: http://www.youtube.com/watch?v=p349tGYXblk&goback=%2Egmr_2683600

My only additional comment regarding rocking curve is that if you can see it working with a 0D source and a 0D detector then what is so hard visualizing the same in 2D with multiple 0D sources in a 2D array and a 2D pixelated detector?

This is precisely at the root of the inability to "resonate" with the community! You certainly helped me articulate it ("spit it out") Alex!

Nano structure in 3D: Tomographic observations of various reciprocal space parameters (e.g., Bragg Peak Shift, Relative FWHM, Relative Integrated Intensity etc.) for individual pixels using multiple (hkl) reflections and Bragg XRD Microscopy. This can be accomplished both in reflection and transmission. This would certainly not be "trivial & simple" for a multi-constituent sintered composite. However, with the right set of analytical tools, achievable or feasible. It is yet to be demonstrated for mono-crystalline wafers. At least as far as I know. Hope to be wrong on this one.

here is the time when I can say "nanananère". Sorry, Ravi but you provided me with such an amount of fun today!

All work and no play makes a dull day! Have fun at my expense. Go ahead Alex! Mirth clearly extends our lives and lubricates communication. There are "laughter clinics" for the elderly in India. There is clear evidence that it works. The "court jester" was as much a part of good governing as was the "crown" in the past. Peace brother!

BTW if you had so much fun, you ought to at least click one of the options right on top of this question with the stats. "Green" or "Red" is immaterial.

Enjoy! Here's some of the best in Americana - http://www.shoutcast.com/shoutcast_popup_player?station_id=152075&play_status=1&stn=GratefulDay - Grateful Dead Complete Liv...

... !!! ...

You are such an hero! And you fail with something like: "My only additional comment regarding rocking curve is that if you can see it working with a 0D source and a 0D detector then what is so hard visualizing the same in 2D with multiple 0D sources in a 2D array and a 2D pixelated detector?" ?

As would say Figaro: "I always first laugh out of situations so I don´t have to cry"

This said, have fun!

I'm still learning your sense of humor Alex. Failure is a precursor (stepping stone) to every success! "I've failed so many different ways that I've finally figured out how not to" - paraphrasing Thomas A. Edison. This was after he had unsuccessfully tried everything conceivable for the "light bulb" filament including hair from the horse's bottom (tail). (Watch it! Don't get mired up in the excrement again. Lol!). Final success came after the introduction of vacuum ("nothing") to prevent oxidation. Send the data!

Later buddy!