Kapanadze and other FE discussion

[stivep]

Answer to mkjekyll:
http://www.magnets.com.cn/Magnetic-powder/dry-pressing-strontium-ferrite-magnetic-materials.html

What is the difference in a magnet that is aligned prior to sintering and one that is not?

No such  thing  as  aligned prior to sintering exists.!!!!
Yes I agree that such term is in use.
Temperature of sintering around 1200C (2192F)must affect magnetization of particles  making the magnet
So when in green stage that magnet is different from the ready to use  one.

for these interested  what sintering is:
process of making (a powdered material) coalesce into a solid or porous mass by heating it (and usually also compressing it) without liquefaction.

The problem  we have here is Curie temperature:In physics and materials science, the Curie temperature
(Tc), or Curie point,

is the temperature at which certain materials lose their permanent magnetic properties,
to be replaced by induced magnetism.
The Curie temperature is named after Pierre Curie, who showed that magnetism was
lost at a critical temperature.

https://en.wikipedia.org/wiki/Curie_temperature

Note to  mkjekyll:
Please note  that anisotropic powder is not grown crystals but mechanically powdered crystals in withing particles.

Wesley

[stivep]

Answer to mkjekyll #2:
some videos  from sintering.
https://www.youtube.com/watch?v=rVyVqtQrjnI   process of heating at temperature below curie temperature

https://www.youtube.com/watch?v=pwOu8Jkjwms this  one is exotic  (  skip it   unless  you  know  what it is)Please note  that magnet wire has  nothing to do with magnet.

https://youtu.be/6hPodO-ZsTY?t=26
https://www.youtube.com/results?search_query=sintering+of+magnethttps://www.youtube.com/watch?v=7-KSDPWw7jU
https://www.youtube.com/watch?v=lJ22svZFGKc - interesting and  educational.
this  is  the green stage
https://www.youtube.com/watch?v=nHjayUoi8L4 much  more primitive   way   to sinter

this video deserves  your attention( starts from given time)
https://youtu.be/jq8WOUFeCcg?t=138 Curie temperature

Wesley

[stivep]

Science  don't want to touch explanation of Avramienko  fork phenomena.
I don't  have time to  write much
I'm preoccupied  with my Electron Microscope
But for these  who read Russian  here it is:
https://drive.google.com/file/d/1rqFe0HVdSqCDitYSLFcpFqyy4cC3loMu/view
Wesley

[stivep]

Assembly of LEO 435VP is going takes me some time.

Some links to EDXRF detector mounted  in   the instrument:
1. https://www.youtube.com/watch?v=WIcTTPffyMw
EDS Inca Calibration

2. https://youtu.be/SdpXFcf_La0?t=929
Energy Dispersive X Ray Spectroscopy

3. https://www.youtube.com/watch?v=xlXEP5yONA0
Introduction to Energy Dispersive X-ray Spectrometry (EDS

I'm in process -of checking connections:
The two HD one in LEO 435VP and one with separate  computer  dedicated to INCA two units:
a.inca mics
b. inca x-stream
Both of them  are being  replaced  with new one.
Yes  I do have shot gun powder residue analysis capability too.
This  is great  for powder  analysis .
Compaction press for the green stage, prior to  sintering is not a problem .
=============================================
working on  crystalline of the ferrite.
We expect new sample to be send from Riga.



Oxford Instruments ISIS 300 EDX spectrometer operating in variable pressure mode at 10
Pascals with an accelerating voltage of 10 kV and a beam current of 500 picoamps for 1000 frames

http://research.engineering.ucdavis.edu/cnm2/wp-content/uploads/sites/11/2017/04/EDXS-SOP_033017.pdf
Oxford Instruments Energy-Dispersive Spectroscopy (EDS) Operating Manual

https://www.ncdoj.gov/getdoc/335a812e-088d-4df5-ac0b-6e5ce8357bd7/SEM-EDX-GSR-ASPEX.aspx - 
Characteristic  Gunshot  Residue Particles.
GSR Casework procedure  manual

http://meteorite.unm.edu/site_media/pdf/SEM_Manual2006.pdf
This is JEOL but it has  manual for Link from ISIS older version

http://eprints.whiterose.ac.uk/114574/9/ASTM%20paper%20Graphite%20in%20Steel%20DVEdmonds_SubmittedMainDocument_newer%20version.pdf
Picture below is an  example of  application.
SEA5120 is university lab grade XRF.
The major advantage  with LEO 435VP is  WDS  technique that is an  addition to traditional EDS


Wesley

[stivep]

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4082842/

components of gunshot residue (GSR), in particular, metallic particles originating from the ammunition primer, reveal characteristic properties and so provide themselves a
high value evidence of using a firearm. Only few particles, of total mass no greater than 100 picograms, can be accepted as the evidence relating an individual with a shooting incident.
The fundamental criterion of the identification of metallic gunshot particles is their chemical contents, that is, rarely occurring set of elements: lead, antimony, and
barium as well as their morphology reflecting the kinetics of the processes undergoing during a gunshot, especially rapid cooling of droplets of the molten metals
present in the expanding plum of products of the primer detonation and the propellant combustion.

In our application violent processes in the ferrite  associated with strong  vibration and sound can be analyzed by analysis of its kinetics - in "after facts".
I'm very careful now, watching every step  to properly estimate any possible side effects .


Wesley