It all depends on whether you are going to study fracture surfaces or polished surface; different info is obtained from those 2.

Some microscopes have the capability of operating under environmental conditions, so no drying or vacuum is involved

Polished samples require mounting in resin, polishing using a water free lubricant and carbon coating; useful for microstructures with chemical contrast using backscattered electron images and energy dispersive spectroscopy for the evaluation of the chemical composition

Fracture surfaces, are useful to obtain topographic information. Wet fracture surfaces allow the observation of the morphology of phases or reaction products without undergoing drying (in the oven or under the vacuum of the microscope column); so phases like ettringite can be seen in their actual morphology

the most important that you need is cold mounting materials that should have viscosity like water to impregnate in hardened cement . mounting material like EPO-TEK 301 and LR White resin are necessary . if such epoxy does not exists , stop the project. these epoxy does not delivered by airline posting, needs cold packing and Expiration date.

A lot of useful information could be obtained from fracture surface of cement.

For obtaining polished cross sections you need to fill pores in cement with low viscosity epoxy (there are a number of them, for example https://www.emsdiasum.com/microscopy/technical/datasheet/14310.aspx). Usual procedure: first step - soaking in dehydrated (100%) ethanol, then in one or two changes of epoxy for prolonged time, then polymerization in an oven.

Article A Low Viscosity Epoxy Resin Embedding Medium for Electron Microscopy

https://ciks.cbt.nist.gov/~garbocz/paper29/node8.html

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.219.1765&rep=rep1&type=pdf

You may also have a look on the following discussion:

https://www.researchgate.net/post/why_the_use_of_MP_as_cement_replacement_with_15_led_to_obtain_on_cement_paste_the_of_Ca_lower_and_the_Fe_Al_higher_than_others_with_5_and_10MP

Thank you for your replay, the informations

and thank you for sharing it with us

@Arash Bayat, @Vladimir Dusevich, and @Lukasz Sadowski

Best Regards

It all depends on whether you are going to study fracture surfaces or polished surface; different info is obtained from those 2.

Some microscopes have the capability of operating under environmental conditions, so no drying or vacuum is involved

Polished samples require mounting in resin, polishing using a water free lubricant and carbon coating; useful for microstructures with chemical contrast using backscattered electron images and energy dispersive spectroscopy for the evaluation of the chemical composition

Fracture surfaces, are useful to obtain topographic information. Wet fracture surfaces allow the observation of the morphology of phases or reaction products without undergoing drying (in the oven or under the vacuum of the microscope column); so phases like ettringite can be seen in their actual morphology

That was great, thanks for your sharing.

@J Ivan Escalante-Garcia

You shine my page by your replies

Thank you very much

Yes, some microscopes have the capability of operating under environmental conditions, so no drying or vacuum is involved

Polished samples require mounting in resin, polishing using a water free lubricant and carbon coating; useful for microstructures with chemical contrast using backscattered electron images and energy dispersive spectroscopy for the evaluation of the chemical composition

The attach file will be helpful for the sample preparation concrete or mortar sample for SEM in (Back scattered Electron Mod )

Many thanks dear Asim.

I endorse J Ivan

Preparation of Cement Paste, Mortar, and Concrete Sections Cement pastes, mortars, and concretes may be prepared in two ways: A) dry potting and B) wet potting. Dry potting is used when the specimen has been dried before, when drying shrinkage related cracking is not of concern, or when a rapid preparation is needed. Wet potting is used to prepare a polished section where the material has not been dried and therefore has not undergone any drying shrinkage. Cracks observed using this preparation may then be ascribed to physical or chemical processes acting upon the concrete, and not due to drying-related shrinkage.

Dry specimen potting involves taking a sawn section or block of material and drying the specimen at low temperature (less than 65 °C). Removal of water is necessary as it can interfere with polymerization of the epoxy. The specimen is then placed in a container and surrounded by epoxy leaving a top surface exposed to the laboratory air, allowing the epoxy to be drawn into the microstructure by capillary suction. To speed the infiltration, the specimen may be completely immersed in epoxy, and a vacuum drawn to remove remaining air. Upon release of the vacuum, the epoxy is forced into the pore system. The epoxy is cured at low temperature (65 °C), and then is ready for the cutting and polishing.

Wet specimen potting is a three-step process where the pore solution is replaced with alcohol (200 proof ethanol), the ethanol is replaced with a low-viscosity epoxy, and then the epoxy is cured. The slab and wafering saws are lubricated with propylene glycol or isopropyl alcohol to keep the specimen from drying when cutting. The cut section is then placed in a lidded jar filled with 200 proof ethanol for the alcohol - pore solution replacement stage. The use of a companion specimen allows one to gauge the time necessary for the alcohol - pore solution replacement. This companion specimen is usually a remnant from the specimen after trimming. This specimen is placed in a jar filled with ethanol dyed a deep red or blue using any alcoholmiscible dye. By splitting or sawing the companion specimen after a period of time, the depth of replacement is seen by the depth of dye coloration. When this front is equal to half the section thickness, the pore solution in the section has been replaced by alcohol. The section is then placed in a container with the low-viscosity epoxy. The time necessary for epoxy replacement of the alcohol is at least equal to that required for the first replacement stage. In our laboratory we provide about 1.5 times the pore solution - alcohol replacement time for that of the epoxy - alcohol replacement. Implicit in this method is that the thinner the section, the shorter time is required for each stage. The specimen is placed in a mold with fresh epoxy, which is then cured at low temperatures according to the manufacturer's directions. The specimen is now ready for the cutting and polishing stages.

from: http://ws680.nist.gov/publication/get_pdf.cfm?pub_id=860297

Thanks a lot dear Boriana, I'm read it.

Thank you for the interesting question

You're welcome dear Mohammed S. Nasr.

Dr Saleh is right. His answer is recommended

Thanks a lot for your contribution dear Dr K N Sheth.

You are welcome, I'm glad I was able to help. Good luck with your research!

Thank you for the question Doha M Al Saffar. Thanks for the answers as well.

You're welcome dear Dr.P. Gomathi Nagajothi.

Regards

Thank you very much Senthil Kumar Kaliyavaradhan.

Doha M Al Saffar … Please check references below.. hope it will be helpful for you…

Regards…

https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/pccp/04150/chapt14.cfm

http://www.metallum.com.br/21cbecimat/CD/PDF/104-001.pdf

Thank you Hussam Ali.

thank you for this equation

thanks Doha M Al Saffar , for the interesting question.

You're welcome dear Dr.Mushtaq Sadiq Radhi

thanks Doha M Al Saffar , for the this question.

Cement pastes, mortars, and concretes may be prepared in two ways: (1) dry potting and (2) wet potting. Dry potting is used when the specimen has been dried before, or when rapid preparation is needed. Wet potting is used to prepare a polished section where the material has not been dried. Cracks observed in wet-potted specimen.

However, cutting, grinding, polishing and epoxy impregnating are most common techniques.