Tarnishing of metal surfaces

Input(s)

$D_{O 2_{M O x}}$: Diffusivity $\left(\mathrm{cm}^{2} / \mathrm{s}\right)$

$\mathrm{t}$: Time (s)

$\mathrm{x}$: Mole Fraction of Oxygen (dimensionless)

$c_{\mathrm{o}}$: Solubility of Oxygen $(\mathrm{g} / \mathrm{cc})$

$\mathrm{c}_{\mathrm{f}}$: Molar Density of the Film $(\mathrm{g} \mathrm{mol} / \mathrm{cc})$

Output(s)

$z_{f}$: Thickness of Film $(\mathrm{cm})$

Formula(s)

$$ \mathrm{z}_{\mathrm{f}}=\left(\left(\frac{2 * \mathrm{D}_{\mathrm{O} 2_{\mathrm{MOx}}} * \mathrm{t} * \mathrm{c}_{\mathrm{o}}}{\mathrm{x} * \mathrm{c}_{\mathrm{f}}}\right)^{0.5}\right) $$

Reference(s)

Bird, R.B., Stewart, W.E. and Lightfoot, E.N. (2002). Transport Phenomena (Second Ed.). John Wiley \& Sons, Chapter: 18, Page: 576.