# Investigation of CuTi Alloy for Applications as Non-Sparking Material
## 3 Results and Discussions
### Electrochemical Corrosion Resistance of CuTi Alloys  
The electrochemical tests were conducted in a saline solution with 3.5% NaCl (laboratory made) to analyze the behavior in possible environments with a salty atmosphere or in various electrolyte solutions with high salinity, such as the marine environment. To ensure the reproducibility of the results, the electrochemical corrosion tests were repeated three times, and the standard deviation was added in Table 2.  
The potentiodynamic polarization curves of Cu-3%wt Ti in saline electrolyte solution are shown in Figure 5, and the corrosion current densities and corrosion potential, obtained by Tafel extrapolation, are presented in Table 2. From the analysis of the curves, it can be seen that there is no significant difference between the behavior of the two different states of the alloy in terms of corrosion resistance and that the curves almost overlap. From the i\({}_{\text{corr}}\) values (Table 2), which are directly related to the corrosion rate by [PERSON]'s law, it can be observed that the cast and rolled samples behaved similarly, with a \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Alloy**} & \multicolumn{2}{c}{**Area**} & \multirow{2}{*}{**General**} & \multirow{2}{*}{**Pct 1**} & \multirow{2}{*}{**Pct 2**} & \multirow{2}{*}{**Pct 3**} & \multirow{2}{*}{**Pct 4**} & \multicolumn{2}{c}{**EDS**} \\  & & & & & & & & **Error\%** \\ \hline \multirow{4}{*}{Cu\({}_{2}\)Ti-cast} & \multirow{2}{*}{Cu} & wt & 97.9 & 93.3 & 98.7 & 99.1 & 97.4 & \multirow{4}{*}{1.5} \\ \cline{3-3} \cline{5-7}  & & at & 97.3 & 91.3 & 98.2 & 98.8 & 96.6 & \\ \cline{2-7}  & \multirow{2}{*}{Ti} & wt & 2.1 & 6.7 & 1.3 & 0.9 & 2.6 & \multirow{2}{*}{0.2} \\ \cline{3-3} \cline{5-7}  & & at & 2.7 & 8.7 & 1.7 & 1.2 & 3.4 & \\ \hline \multirow{4}{*}{Cu\({}_{3}\)Ti-hot rolled} & \multirow{2}{*}{Cu} & wt & 97.4 & 97.5 & 96.3 & 97.7 & 85.8 & \multirow{4}{*}{2} \\ \cline{3-3} \cline{5-7}  & & at & 96.5 & 96.7 & 95.2 & 96.9 & 82.1 & \\ \cline{2-7}  & \multirow{2}{*}{Ti} & wt & 2.65 & 2.5 & 3.7 & 2.3 & 14.2 & \\ \cline{3-3} \cline{5-7}  & & at & 3.5 & 3.3 & 4.8 & 3.1 & 18.0 & \\ \hline \hline \end{tabular}  
* St. Dev.: Cu \(\pm\) 1.2; Ti \(\pm\) 0.1.  
\end{table} 
Table 1: Chemical composition of alloys. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Sample**} & \multirow{2}{*}{**E (I = 0)**} & \multirow{2}{*}{**i\({}_{\text{corr}}\)**} & \multirow{2}{*}{**Rp**} & \multirow{2}{*}{**V\({}_{\text{cor}}\)**} & \multirow{2}{*}{\(-\beta_{\text{c}}\)} & \multirow{2}{*}{\(\beta_{\text{a}}\)**} \\  & & **(mV)** & & & & & \\ \hline Cu\({}_{3}\)Ti (Cast) & \(-\)287.5 & 14.5790 & 1.60 & 168.5 (\(\pm\)0.45) & 239.1 & 128.0 \\ Cu\({}_{3}\)Ti (Hot-rolled) & \(-\)319.6 & 15.0904 & 2.54 & 174.4 (\(\pm\)0.64) & 265.5 & 157.2 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Characteristic electro-chemical parameters of the linear potentiometry test (with Tafel interpretation). slight increase in the corrosion rate for the rolled sample, caused by the induced stresses in the material by hot rolling. The evolution laws of corrosion resistance under different metastable phase morphology and size conditions are still unknown. Some studies revealed that the presence of the incoherent secondary phases could decrease the corrosion resistance [26,27], while others showed that corrosion could be restrained by controlling the morphology and distribution of the metastable phase by plastic deformation [28, 29, 30]. The E\({}_{\text{corr}}\) corrosion potential values were substantially similar. Cyclic potentiometry (Figure 5b) showed a general corrosion pattern of CuTi alloys in saline solutions with a slightly higher current density of the rolled alloy compared to the cast one. Subsequent LOM and SEM analysis confirmed the general corrosion type. Chlorine and oxygen-based compounds were identified on both the cast and hot-rolled samples.