Seminar Schedule – Spring 2019

Thursday, March 7, 2019
Time: 3:30pm – 5:00pm
Place: ASE 1.126

Probing defect-controlled plasticity at small scale via multiscale discrete defect element method (DDEM)

Ill Ryu, University of Texas at Dallas

Nanotechnology attracts much attention due to not only its useful engineering applications, but also their superior material performances. As the dimensions of the devices become smaller and smaller, however, understanding the mechanical properties of materials at sub-micron length scales becomes more challenging. For the reliable design of MEMS or NEMS devices, nanotechnology has always called for an understanding of the mechanical behaviors of materials at small length scales.

In this talk, size dependent plasticity in metallic micropillars will be discussed in terms of dislocation mechanics. Considering dislocation sources from the surface, micropillar plasticity will be analyzed using meso-scale dislocation dynamics model to understand how dislocation behavior relates to mechanical response in metals. In addition, the multiscale defect element method (DDEM) method has developed to couple conventional continuum crystal plasticity finite element (CPFEM) with a discrete defect (DD) modeling. The proposed model could account for complex multi-physical phenomena, which would play an important role in obtaining a fundamental understanding of deformation mechanism at small scale. The unified concurrent coupled model will shed light on fundamental investigation of defect-controlled mechanical behaviors in crystalline materials, such as plasticity and heat flow and damage.

For further information, please contact Dr. Rui Huang at ruihuang@mail.utexas.edu or (512) 471-7558.