I am trying to study the mechanical properties of shales by Atomic Force Microscopy (AFM) nanoindentation. However, I have had some problems with measurements becuase some minerals (which compose the shale matrix) are so hard for instrumental sensitivity.
Has anyone measured shales mechanical properties by this technique?. Could you share you experience?
dear colleague : thank you for this question
for resolving this problem ( minerals ) you can a first traited shales by acid solution ( HCL 1M or H2SO4 1M ) at 60°C in 30 minutes.
best regards
In general, it is better to use special nanoindentation instruments to examine such hard objects. In AFM the applied force is limited with cantilever stiffness (force constant) and cannot be very high. It is possible to try it with a very hard (up to 100 N/m) cantilever, perhaps it will be enough for indentation, but it is very likely that the tip or cantilever will be damaged. I would find a nanoindentation system around rather than torture the AFM.
Good luck!
You will run out of luck when indenting hard material with a rather compliant mechanical test system, such as the AFM-based nanoindentation mentioned. However, if you could lower the stiffness of the test specimen, then it is possible. For instance, you could employ focused-ion beam system to fabricate micro-pillar or micro-cantilever, then using the AFM to compress/bend the much smaller specimen.
Hi, Simon!
We studied the mechanical properties of salt rock crystals on the AFM. If this is interesting for you, I can give links to articles.
Best regards.
- Badges
- Science topic