October 18, 2013 |
11 a.m.-12:30 p.m.
Nedderman Hall, Room 100 | Seminar Flyer
Assistant Professor, The University of North Texas Department of Materials Science and Engineering.
Refreshments served at 10:40 a.m.
Abstract: Nanoindentation techniques have been used to understand micro scale plasticity in crystalline materials. Atomistic modeling is a useful tool to complement these experimental studies by revealing atomistic level activities of defects, particularly dislocations. In this talk, we will present different nucleation and interaction induced by nano indentation in face-centered cubic (FCC) metals, and how these dislocations activities lead to 1) different surface deformation profiles that can be observed and measured, and 2) size effects due to dislocation-grain boundary interactions. These results demonstrate that micro scale deformation is closely related to crystalline structure and also micro structural features such as grain boundaries.
Bio: Zhiqiang Wang, assistant professor, joined the Department of Materials Science and Engineering at the University of North Texas in 2009. He has a Ph.D. in mechanics and mechanical engineering from UCLA. His expertise is in developing advanced multi scale modeling techniques, including three-dimensional dislocation dynamics, molecular dynamics, and finite element analysis, to understand defects and microstructures in materials, and to predict the structure-relationship of engineering materials. He worked as a postdoctoral researcher at Los Alamos National Laboratory, working modeling the high-strain rate deformation of metals. He is currently interested in studying the fracture, fatigue, strength and failure of Ni-based superalloys, Al alloys, metal matrix composites, and other FCC/BCC/HCP materials.