Dislocation source activation at grain boundaries
While several methods are well-suited for studying dislocation transmission through grain boundaries, a quantitative approach understanding dislocation source activation in grain boundaries is currently lacking.
Within this work we are aiming for developing a test protocol, which can provide a statistical significant, quantitative measure for the dislocation source activation at grain boundaries.
For this purpose we apply several different experimental micromechanical techniques on pure copper bi-crystals. For instance nanoindentation, using a spherical nanoindenter, is used to obtain differences in the pop-in behavior of bulk single crystals and their fine grained counter bodies. The attached figure shows the variation of pop-in forces depending on the dislocation density of the material.
Pop-in statistics: The cummulative probability of a certain pop-in force is given for copper with three different dislocation densities.
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