Dual Current Density (DCD) Example Calculations:

There are several configurations that can occur while solving curves where the Dual Current Density Method and these all had to be programmed into the software.  However, calculations are provided here for solving for the most typical configuration and that shown in Figures 16 and 17, namely, where there is a cuprous inflection point before the transition and a cupric inflection point afterward. 


            Cuprous Thickness  = εcuprous  *  Kcuprous  * tcuprous * CDinitial

            Cupric Thickness  =  εcupric  *  Kcupric  ((ttransition  -  tcuprous) CDinitial 

+  (tcupric  -  ttransition) CDfinal)

            Total Thickness =  CDinitial  cuprous  *  Kcuprous  * tcuprous  

+  εcupric  * Kcupric  * (ttransition  -  tcuprous) )  

+ CDfinal * εcupric  * Kcupric  (tcupric  -  ttransition                 [5]


where CDinitial  and CDfinal are the initial and final current densities, respectively and ttransition is the time at which the transition occurs during the test. 


(Basic details about our Surface Oxide Tester are found at this link.)