Welcome
Content
Assessment
Diploma
Requested
Applying
Goodies
Teachers
Acknowledgements



Students

Free Sample








 

QTA Internet Course



Aims

This course aims at providing the knowledge and the tools to quantitatively determine the crystallographic texture of a known crystalline single- or poly-phased sample from powder diffraction data, and to show on few examples how the texture dominates the properties.
Quantitative Texture Analysis (QTA) is still not a routine procedure, particularly for polyphased samples, and a lot is currently under development (see some examples at IUCr site). The ways of carrying a complete texture analysis are often sample dependent, and a lot of experimental mistakes can insert the job.

Texture means that an orientation distribution of crystallites is present: the material of concerns is between a pure powder (with a perfectly random distribution of its individual crystals) and a perfect single-crystal (with only one pure orientation, and without any distribution). While a perfect single-crystal does not exist, a perfect powder can sometimes be fabricated. However, most of the times, the elaboration processes (thin film deposition, synthesis under magnetic field or uniaxial pressure, natural processes ...) give rise to the development of texture, which is then important to characterise. If the sample can be destroyed and if the texture is not important, grinding it and using the usual characterisation tools may suffise. For instance, powder diffraction experiments will allow the usual Rietveld or other refinement strategies. Otherwise, if your sample or if the texture is precious for you, this course may be of interest.  

At the end of this course, it is expected that the candidates will be able to recognise qualitatively a texture, propose a methodology to characterise it, refine a full quantitative Orientation Distribution Function (ODF) and interpret it for the final examination stage. We estimate that a normal duration for passing the exam would be around 15 weeks of intensive learning. However, peoples that work aside (students, professionals ...) may necessitate more, and the duration will not be a parameter. The rules will be:
- Download the first literature for the first chapter, which contains practical examples, and the associated programs
- Study it, take your time and assimilate, ask questions interactively, as many as you want
- You think you are ready, ask for exercises
- Distribution of exercises (generally real cases), try to solve and come back with results
- Your results are corrected and corrections are opportunities for deeper discussions and questions
- When you feel ok, ask for the marked exercises, when received, elaborate the response and send back
- A mark (0 to 20) is assigned
- Download the second literature ...
- ... etc for every chapter ...
- Final exam: an example which can combine all of the previous stuff. A mark is assigned (0 to 20)
- You pass your diploma if exercises (mean of them counts 50% in weight) + exam (the other 50%) are more than 20/40.


 




Comments and suggestions are very welcome
© 2000 - All rights reserved Daniel Chateigner