Recession rate, corrosion

The parameter of interest is then the recession rate, which is identical to k of Eq. (6) for linear kinetics. In corrosion science the Sl-units ms" or the more vivid unit mm year" of engineering practice are useful. The relation to mass loss is obtained by multiplying by the density of the lost material to yield kgm s" or equivalent units. 

With /ti being the metal recession rate constant due to the corrosion process, the critical concentration of an alloying element for different situations of protective behavior can be calculated [19], as illustrated in the graph in Figure 13.8, as a function of the ratio. 

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