|About this Abstract
||MS&T21: Materials Science & Technology
||Probing Defect Properties and Behavior under Mechanical Deformation and Extreme Conditions
||Defect Absorption at Grain Boundaries: A Grain Boundary Structure Perspective
||David Joseph Srolovitz, Jian Han, Larissa Woryk, Mitra Taheri, Jaime Marian
|On-Site Speaker (Planned)
||David Joseph Srolovitz
The absorption of point defects and dislocation loops at a grain boundary (GB)inevitably modifies the GB structure. We present recent atomistic simulation and theoretical results on how grain boundaries accommodate defect absorption. We explore this through the concepts of metastable GB states and disconnections (defects on the GB plane that have both step and dislocation character). We show how absorption of point defects can lead to phase transitions in the GB and how continued absorption leads to periodic cycling between GB states. Next, we examine the evolution of dislocation loops following their absorption at GBs. In particular, we observe how lattice dislocations decompose into GB line defects and the faults between these. The line defects are analyzed in terms of disconnections and GB partial disconnections and the faults between these in terms of metastable GB states.