## 3 Results and Discussions  
As has been explained in Section 2, the dependent variable is the time to failure for the varied load. The load at the end of the arm (see Figure 2) was varied at 8, 10, 12, 14, 16, 18, 20, 22, and 24 kg, which can be converted into the tensile load for the specimen as follows: 115, 144, 173, 201, 230, 259, 288, 316, and 345 MPa, respectively. For each variation of load, three data of time to failure were recorded. In practice, the data were recorded in hours, minutes, and seconds, but for easy data processing they are tabulated in minutes. As an example, two hours, ten minutes, and thirty seconds are tabulated as 120 minutes, 10 minutes, and 0.5 minutes, which equals 130.5 minutes. The complete recorded data are presented in Table 3 that shows the time to failure for varied surface preparation and load when the joint is exposed to the corrosive environment. When a load of 24 kg (345 MPa tensile stress) was applied, the welded joints failed immediately, since the load exceeded the ultimate strength of all joints. The \(\alpha\)1 specimen revived around 5 minutes when 22 kg (316 MPa tensile stress) was applied whilst failure took place directly for two other specimens: \(\alpha\)0 and \(\alpha\)2. The 22 kg load roughly proved that the \(\alpha\)1 specimen was the strongest joint by means of SCC threshold. The time to fail for the \(\alpha\)1 specimen was obtained from three of \(\alpha\)1 specimens to provide statistical acceptable data. The 316 MPa was considered to exceed the ultimate tensile strength of \(\alpha\)0 and \(\alpha\)2 specimens. When 250 MPa was applied, only the \(\alpha\)0 specimen broke instantaneously while the others stood for a certain time, which more or less proved that the modified surface preparation improved the strength of the indigenous flat interfaces welded joint. Figure 2: The stress corrosion cracking (SCC) apparatus. Table 3 represents in graph form what is depicted in Figure 3. For each treatment (certain load and surface preparation), data from three specimens were recorded. The first specimen, namely Spec 1, is represented using square symbols whilst the second and the third specimens, i.e., Spec 2 and Spec 3, are plotted using reversed triangles and cross symbols, respectively. Specimens without surface preparation, i.e., \(\alpha\)0 specimen, are drawn in red color, whilst specimens with sharpened steel and sharpened brass are shown in red and blue colors, respectively. From Figure 3, it can be concluded that the modification of the surface geometry does increase the resilience of the CDW joints to the SCC, which both the \(\alpha\)1 and \(\alpha\)2 specimens exhibited with a better performance on the SCC load compared to the flat interfaces of \(\alpha\)0. For the \(\alpha\)0 specimen, the stress corrosion cracking threshold can be assumed with 112 MPa, and for the \(\alpha\)1 and \(\alpha\)2 specimens with 227 MPa and 170 MPa, respectively, which shows the modified interfaces improve the SCC resilience significantly. The reason of the better performance,  
\begin{table} \begin{tabular}{c} **Mean** \\ **(minute)** \\ \end{tabular}  \\ \hline
8 & \(115\) & \begin{tabular}{c} 180.75 \\ 183.67 \\ 187.63 \\ \end{tabular}  & 184.02 & \ \begin{tabular}{c} - \\ - \\ \end{tabular}  & \begin{tabular}{c} N/A \\ - \\ - \\ - \\ \end{tabular}  & N/A \\ \hline
10 & \(144\) & \begin{tabular}{c} 37.17 \\ 36.67 \\ 35.38 \\ \end{tabular}  & 36.41 & \ \begin{tabular}{c} - \\ - \\ - \\ \end{tabular}  & N/A & \begin{tabular}{c} - \\ - \\ - \\ \end{tabular}  & N/A \\ \hline
12 & \(173\) & \begin{tabular}{c} 17.72 \\ 17.22 \\ 16.83 \\ \end{tabular}  & 17.26 & \ \begin{tabular}{c} - \\ - \\ - \\ \end{tabular}  & N/A & \begin{tabular}{c} 179.50 \\ 180.48 \\ 181.07 \\ \end{tabular}  & 180.35 \\ \hline
14 & \(201\) & \begin{tabular}{c} 7.85 \\ 7.37 \\ 7.18 \\ \end{tabular}  & 7.47 & \ \begin{tabular}{c} - \\ - \\ - \\ \end{tabular}  & N/A & \begin{tabular}{c} 31.33 \\ 30.68 \\ 31.83 \\ \end{tabular}  & 31.28 \\ \hline
16 & \(230\) &