|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Advanced Characterization Techniques for Quantifying and Modeling Deformation Mechanisms
||Modeling Dislocation Arrays in Orientation Gradient Microstructures in Ta Thin Films
||Elizabeth Ellis, Ari Kestenbaum, Shefford P. Baker
|On-Site Speaker (Planned)
Tantalum films are widely used in industry, in such applications as thin film capacitors and resistors. When Ta is deposited in the metastable beta phase and then annealed to transform to the stable alpha phase, an unusual microstructure arises: EBSD results show that the orientation of these films rotates continuously through large angles across the film. In order to understand this structure, we have tried to predict the types of dislocations which may give rise to this microstructure. While a Nye tensor approach was not successful for calculating geometrically necessary dislocations directly from EBSD data, a simple model showed that our microstructure can be replicated using a simple rotation scheme. Expanding on this, we developed a genetic algorithm to analyze the dislocations associated with our orientation gradient microstructure and found several recurring features. Based on these findings, we comment on the origin and development of this unique microstructure.
||Planned: Supplemental Proceedings volume