|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Advanced Thermo-mechanical Characterization of Materials with Special Emphasis on In Situ Techniques
||Dislocation Drag Coefficient Measurements via In-situ Micropillar Compression Experiments
||Tommaso Giovannini, Finn Giuliani, Daniel Balint, Ayan Bhowmik
|On-Site Speaker (Planned)
The dislocation drag coefficient is a quantity that provides a quantitative measure of dislocation mobility in crystalline materials. It is a key input to dislocation dynamics models, which are used for making predictions on the microstructural mechanisms that govern deformation. Molecular dynamics simulation is the most common method of estimating the drag coefficient in many materials, as experimental attempts are difficult to perform on individual defects. Moreover, experimental results often show considerable difference with computational estimates. A method is proposed in which the drag coefficient, in an oriented zinc single crystal, is measured during an in-situ micropillar compression experiment. Slip is activated on a single system by orienting the single crystal substrate to provide a favourable Schmid factor configuration. By measuring the slip velocity corresponding to different resolved shear stresses, it is then possible to measure the drag coefficient directly as the gradient of a linear fit to the data.
||Planned: Supplemental Proceedings volume