Carbon is a common specimen contamination in a SEM chamber (from oil of vacuum pumps). If you see a lot of carbon, it could be something in your concrete. Check in multiple points.
Carbon is a common specimen contamination in a SEM chamber (from oil of vacuum pumps). If you see a lot of carbon, it could be something in your concrete. Check in multiple points.
Agree with V.Dusevich. First thing is to check for carbon deposition/contamination.
However, some concrete formulations may use polymers as additives : acquire elemental maps of your sample (play with the accelerating voltage to see if you can contrast Carbon better) and see if there's a pattern or not (is Carbon present between the oxides structures ?).
Dear Deep, I agree with V. Dusevich. Additionally I recommend to carry out the following experiment:
Select a "fresh" sample, it can be a metal plate which never was within a microscope. The surface must be clean (aceton). If you detect carbon, no signal must be observed. Then you wait for 30 minutes or so. If you have contaminations from cracked oil, the carbon signal increases with time.
With regard
R. Mitdank
Presence of carbon is detected may be due to the possible occurrence of solidified organic matter inside the concrete.
To add to what otuers have pointed out, concrete is non-condicting. So we use soutter coats and sometimes, Carbon tape to hold the specimens in position on the stage. That can be a source of Carbon, which needs to be removed from the spectra. Carbon is *NOT* a part of hydrated cement paste. There maybe contamination and there maybe absorption of carbon dioxide over the years in concrete. So, matured samoles collected from aged structures might show Carbon. A non-contaminnated freshly hardened paste is unlikely to show Carbon.
As already mentioned, presence of some polyners might lead to Carbon presence. Another possible source could be carbonate precipitation in bacterial concrete.
Energy dispersive X-ray spectroscopy (EDS) is a microanalysis technique for material characterization that can provide accurate quantification of elemental composition while maintaining high spatial resolution.
- Badges
- Science topic