## 3 Results and Discussion
This agrees well with the results of the corrosion rate calculations based on the analysis of the polarisation curves carried out using the Mansfeld method (Table 2). The same results were obtained during the salt spray testing (Table 4). The period when the first signs of corrosion attack appear \(\tau_{\mathrm{corr}}\), with the inhibitor concentration within the range of 1 to 10 mM, is longer and can be presented as follows: inhibitor A \(<\) inhibitor B \(<\) inhibitor C \(<\) inhibitor D. \(\tau_{\mathrm{corr}}\) increases with higher \(C_{\mathrm{inh}}\) and reaches 2-4 days at 10 mM, which proves the effectiveness of 3-sulphhylalkyl derivatives of 5-amino-1H-1,2,4-triazole  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Inhibitor** & \(C_{\mathrm{inh}}\), **mM** & \( \begin{array}{c}R_{\Omega_{\mathrm{r}}}\\ \Omega\cdot\mathbf{cm^{2}}\end{array} \) & \( \begin{array}{c}\mathbf{CPE}\\ Y_{\omega}\\ \Omega^{-1}\cdot\mathbf{cm^{-2}}\cdot\mathbf{s}\end{array} \) & \(n\) & \(\begin{array}{c}\mathbf{R_{P}}^{\mathrm{HS  
A series of full-scale natural corrosion tests in 1% HCl solution demonstrated that with a higher concentration of the inhibitor and the growth of the chain, the additive the rate of copper corrosion decreases. The highest protection level of up to 90% results from inhibitor D at any concentration within the range of 0.01 to 1.00 mM. Additional proof is provided by the images of the surface of copper electrodes held in the salt spray chamber (Figure 4). In the presence of the inhibitor, the surface of the copper electrode remains bright and smooth even if the concentration of the organic additive is minimal (Figure 4c). Without the inhibitors, the surface of the electrode darkens (Figure 4b) and corrosion spots appear. To explain this effect, we carried out scanning electron microscopy and analysed the micrographs of the copper electrode surface taken before and after potentiodynamic anodic polarisation in a neutral chloride solution (Figure 5). Without the inhibitors, multiple corrosion spots of about 5-10 mM appear on the surface. However, when the copper is polarised in the solution with 1 mM of 3-phenethylsulphinyl-5-amino-1\(H\)-1,2,4-triazole (inhibitor D), no pits can be observed on the surface. The micrographs only show scratches left from polishing the electrode. \begin{table}
\begin{tabular}{c c c c c c} \hline
**Inhibitor** & \(C_{\text{inh}}\)**, mM** & \(k\)**, g/m\({}^{2}\)/day\({}^{-1}\)** & \(\Upsilon\) & \(Z_{\chi}\)**, \%** & \(\tau_{\text{corr}}\)**, h** \\ \hline - & - & 44 & - & - & 1-2 \\ \hline \multirow{4}{*}{A} & 1.0 & 17.3 & 1.3 & 22.9 & 26 \\  & 5.0 & 13.7 & 1.6 & 38.9 & 43 \\  & 10.0 & 10.3 & 2.2 & 54.1 & 43 \\ \hline \multirow{4}{*}{B} & 1.0 & 18.4 & 1.2 & 17.8 & 47 \\  & 5.0 & 5.9 & 3.8 & 73.9 & 63 \\  & 10.0 & 4.3 & 5.2 & 80.9 & 63 \\ \hline \multirow{4}{*}{C} & 1.0 & 22.4 & 1.0 & 0.0 & 68 \\  & 5.0 & 4.7 & 4.8 & 79.0 & 86 \\  & 10.0 & 2.3 & 9.8 & 89.8 & 117 \\ \hline \multirow{4}{*}{D} & 1.0 & 0,9 & 10,9 & 90,8 & 70 \\  & 5.0 & 0,7 & 13,1 & 92,4 & 95 \\ \cline{1-1}  & 10.0 & 1,5 & 6,4 & 84,3 & 100 \\ \hline \end{tabular}
\end{table} 
Table 4: Results of the copper natural corrosion tests. Figure 4: Copper samples before (**A**) and after salt spray corrosion testing without an inhibitor (**B**) and in the presence of 3-phenethylsulphinyl-5-amino-1\(H\)-1,2,4-triazole at concentrations of 0.01 (**C**), 0.10 (**D**), 1.00 mM (**E**). The results of the analysis of the elemental composition of the surface layer of the copper electrode before and after anodic polarisation are given in Table 5. Quite notably, the introduction of the organic additives results in a significant decrease in the amount of oxygen on the copper surface, which may be accounted for by the fact that the metal oxidation slows down due to the slowdown of the anodic process.