Materials Science and Engineering: An Introduction

Published by Wiley
ISBN 10: 1118324579
ISBN 13: 978-1-11832-457-8

Chapter 17 - Corrosion and Degradation of Materials - Questions and Problems - Page 721: 17.13b


K = 0.129

Work Step by Step

Calculating the value of K in order to give the CPR in mpy for i in µA/cm2 (10-6 A/cm2), note that the units of A (in µA/cm2 ) are amperes or C/s. Substitution of the units normally used into the former CPR expression above leads to: CPR = K' $\frac{Ai}{nFp}$ CPR = K' $\frac{(\frac{g}{mol}) (C/s - cm^{2})}{(unitless)(\frac{c}{mol})(\frac{g}{cm^{3}})}$ = $\frac{cm}{s}$ Finding CPR in mpy and as i is given in $\frac{ µA}{cm^{2}}$ and for K = $\frac{K'}{F}$, K = ($\frac{1}{96,500 \frac{C}{mol}}$) ($\frac{10^{-6}C}{µC}$)($\frac{1 in}{2.54 cm}$)($\frac{10^{3}mil}{in}$)($\frac{3.1536 \times 10^{7} s}{yr}$) K = 0.129
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.