Lecture

Physically Based Constitutive Models

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In course

ME-628: High Strain Rate Mechanics of Materials

This course offers fundamentals concepts of material behavior under dynamic loads such as impact and shock. lt will cover experimental methods and analytical modeling approaches to describe the dynamic deformation behavior of metals, ceramics and polymeric ...

Description

This lecture covers the development of constitutive models based on physical principles, focusing on the high strain rate behavior of materials and the evolving microstructure during deformation. It discusses the obstacles dislocations face, such as Peierls-Nabarro forces, and the role of thermal energy in dislocation motion. The lecture also explores the rate dependency of plastic response, the interaction of dislocations with defects, and the constitutive equations derived from activation barriers. Additionally, it delves into the strain rate sensitivity of materials and the evolving microstructure's impact on stress-strain behavior.

Official source

Ontological neighbourhood

Chemical engineering

Materials science: Deformation of materials

Related concepts (32)

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Biodegradable plastic

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Dislocation

In materials science, a dislocation or Taylor's dislocation is a linear crystallographic defect or irregularity within a crystal structure that contains an abrupt change in the arrangement of atoms. The movement of dislocations allow atoms to slide over each other at low stress levels and is known as glide or slip. The crystalline order is restored on either side of a glide dislocation but the atoms on one side have moved by one position. The crystalline order is not fully restored with a partial dislocation.

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