Patterns of plastic flow in sheared polycrystalline solid

Date

May 16, 2014

Time

9:20 AM - 10:20 AM

Speaker

Anirban Sain

Affiliation

IIT Bombay, India

Language

en

Main Topic

Mathematik

Other Topics

Mathematik

Host

Prof. Dr. A Voigt

Description

Crystalline solids undergo plastic deformation and subsequently flow when subjected to stresses beyond their elastic limit. In nature most crystalline solids exist in polycrystalline form. Understanding plastic flows in polycrystalline solids is important for material processing. Simulating phase field crystal (PFC) model we show that in sheared polycrystalline solids the atomic displacement field is highly heterogeneous, similar to that in amorphous solids. The displacement field also exhibits localized quadrupolar patterns, characteristic of two dislocations of the opposite sign approaching each other. This is a signature of crystallinity at microscopic scale. Polycrystals being halfway between single crystals and amorphous solids, in terms of the degree of structural order, descriptions of solid mechanics at two widely different scales, namely continuum plastic flow and discrete dislocation dynamics turns out to be necessary here.

Links

• Forschungsseminar des Instituts für Wissenschaftliches Rechnen

Last modified: May 12, 2014, 3:54:04 PM