The hydration rate of cement is tipilcally followed through the formation of specific phases that are formed along hydration. So thes phases, as well as other phases from the cement and its texture can be studied and analyzed by conventional SEM techniques, secondary and backscatered electrons, EBSD and EDX. As usual, you should prepare the samples in polyshed conditions in order to apply these techniques, and then is when a hard problem arises: Sample is strongly hygroscopic and cannot be polished with water. Then solution is to develop all the procedure using alcohol instead of water. In this case is better to use ethilic alcohol, because methilic is toxic. In any case it is not an easy task. We have used this method and it works !
Be careful to don't became drunk with the alcohol vapors.
I believe Mr Kahraman and Juan may have answered the topics you need to know.
Preparing your sample appropriately is essential. For analysis of each different texture you may take a SEM image with secondary electron. Then focus the part you want to know the material composition by taking an EDX image.
As has been said already, you can follow the degree of hydration using Backscattered electron imaging of a polished cross-section. Image analysis based on the greyscale should then allow you to identify the different components (pores, C-S-H, portlandite and anhydrous material). If you have a composite cement then things are a bit more complex. With a slag cement, you can record an EDX map to locate the magnesium. This will give you the location of the slag at the onset of hydration (since magnesium is immobile). You then perform an overlay function to separate the anhydrous slag from the magnesium location to give you the degree of slag hydration.
For good statistics, you will need to record a minimum of 30 images per sample, ideally ~50.
Note that this approach is not very accurate for very early stages of hydration because it tends to over-estimate the degree of hydration.
You can find more information in the PhD thesis or paper linked to below.
http://etheses.whiterose.ac.uk/9307/
Article The role of the alumina content of slag, plus the presence o...
I am harsha and I am also doing the same work that you are doing, I will add you a paper hope it is helpful, you can use Fiji software for that, hope it is helpful for you.