Abstract
In this report, the experiments were carried on Fe-Mn, Fe-C-Mn and Fe-C-Mn-Cr alloys with respect to the following items: (1) the change of HCl (37%) quantity in the 3% Cu(NH4)2Cl4·2H2O solution, (2) the relation between optimum replica solutions and corrosive reduction by HCl, (3) the concentration of Cu••, H• and Cl′, (4) the relation between optimum replica solution and structure of alloys and (5) the compositions of replica solution on the Fe-C-Mn and Fe-C-Mn-Cr alloys.
The used samples are shown on the Table 1 and Table 2. The results of experiments are shown in the Table 3 and Table 4. On the chemical plating, some relations are found between the ions of Cu••, H• and Cl′ in the replica solution which varies according to the concentrations of Mn in the iron. Substituting the concentration of H• and Cl′ with HCl quantity, these relations are shown in the Fig. 1. In the figure, the newly gaind HCl curve is symmetrical to the corrosive reduction curve against the streight line which is kept 2.8/4.9. The replica solutions which content HCl quantity in the range of 1.55 to 2.17 cc can be replaced in the structure of many Fe-Mn alloys except γ. And γ structure is replaced by means of replica solutions which contain about 20 cc of HCl quantity next, HCl quantites in the replica solution for Fe-C-Mn and Fe-C-Mn-Cr alloys are shown by the mean value of HCl quantities which were used in the case of replica of every Fe-C, Fe-Mn and Fe-Cr alloys.
