Question

The flow curve for a certain metal has parameters: strain-hardening

Answer 1

Answer:(a)$45,300.24 lb/in/^2$

(b)0.255

Explanation:

Given

Strain hardening exponent(n)=0.22

Strength coefficient(k)$=54000 lb/in/^2$

and we know

$\sigma =k\left ( \epsilon \right )^n$

where

$sigma =true\ stress$

$\epsilon =true\ strain$

(a)True strain=0.45

$\sigma =54000\times 0.45^{0.22}$

$\sigma =45,300.24 lb/in^2$

(b)true stress$=40,000 lb/in^2$

$40000=54000\times \epsilon ^{0.22}$

$\epsilon ^{0.22}=0.7407$

$\epsilon =0.7407^{4.5454}=0.255$