Chapter 6, Problem 6.23P

Interpretation Introduction

Interpretation:

The relation between true strain (e) and engineering strain (e) for the expression $\epsilon =\ln (1+e)$ is to be derived. It is assumed that this expression is not valid after the onset of necking.

Concept introduction:

Concept of strain will be used for the derivation of expression $\epsilon =\ln (1+e)$. The formula of true strain is -

$\epsilon =\ln \left(\frac{l}{l_o}\right)$

The formula of engineering strain is-

$e=\frac{\Delta l}{l}$