The conventional formulation of GNDs generated due to CTE mismatch gives a very high number of several orders. In practicality, is the density of GNDs at the interface of a particle that high? has anyone tried to measure the dislocation density using any of the available characterization methods like TEM or XRD?
Even if the density of dislocations is high at the particle-matrix interface, are these dislocations effective in elevating the yield strength of the material, or is it just a local phenomenon that can only affect the nano/microscale performance of the material like nanoindentation hardness?
Dear Shishir Keerti,
As you know, the dissimilarity in the CTE is responsible for the generation of geometrically necessary dislocations in composites. This large difference in CTE induces thermal residual stress and thus privileges for an improvement in YS.
It is a local phenomenon and In fact, it is the root cause of the failure of material if such GNDs density is low. Dislocation pinning and dislocation pile-up phenomena favour better strengthening and yield strength.
This paper may help you to understand more about dislocation, TEM analysis etc.
Article Characteristics and mechanical properties of magnesium matri...
Thank you.
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