Let's discuss an interesting topic and share ideas on the following question:
which method do you prefer to track damage in a composite material or a bonded joint?
There are different known methods such as strain measurement by the strain gauges, piezoelectric sensors, DIC, optical fibers, and X-ray tomography.
So, please give a feedback on your opinion about the advantages, disadvantageous, and any challenges faced with each method. Tell me about your experience...
please read Article Damage mechanisms in composite bonded joints under fatigue loading
Article Crack propagation analysis in composite bonded joints under ...
Article Fatigue crack growth simulation in adhesively bonded composite joints
There is no "one-for-all" solution to this problem. I would say a combination of one physical (e.g. distributed fiber optic sensors based on Rayleigh backscattering) and one contactless (e.g. DIC) system would work better than a single solution. It is generally tricky to accurately identify minute differences of strains via DIC due to the noisy nature of deriving the displacements. Crack gauges are also nice to have as an additional source of information.
Dear Dr. Akula Komuraiah ,
Thank you for the info. The papers you mentioned are interesting ones within this topic
Dear Dr. Yunus Emre Harmanci
I appreciate for your reply. You're right. Selection of an approach to detect damage significantly depends on the material type and its behavior under specified loading conditions. I myself have performed such an investigation using strain gauge measurement on metal to composite bonded joints. However, your suggestion (distributed fiber optic sensors) seems interesting for such an application.
Regards
If your desire is to “visualize” micro-cracks, nothing will do the job as well as CT (computer assisted x-ray tomography). One concern: most ceramics are not solid structures (per se’), once fired. There is often space between the ceramic particles that was occupied by binder (per firing). Cracks will, of course, travel from open space to open space. Therefore, it may be difficult to recognize very small cracks within the CT, 3-D image data. But larger crack will be easily identified and will be quantifiable via the CT analysis software as voids compared to the solid material. Too, any remaining binder will be quantifiable. And the morphology should tell you if micro cracks are in any way associated with remaining binder. One will also be able to quantify porosity against the solid structure (again, done with the CT analysis software). It is amazing what can be learned from CT, 3D data.