# Experimental Analysis of Welded Rods with a Functionally Graded Material Approach
## 4 Conclusions  
The data obtained as a result of the experimental analysis carried out within the scope of this study reveal the pros and cons of the conventional electric arc welding process compared to the friction welding process. The experimental results regarding the electric arc welding process reveal that the modulus of elasticity is affected by a small amount of high temperature applied during the process. The data obtained as a result of the tensile test reveals that the toughness value obtained from the  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Material** & **Property** & \(\mathbf{P_{-1}}\) & \(\mathbf{P_{0}}\) & \(\mathbf{P_{1}}\) & \(\mathbf{P_{2}}\) & \(\mathbf{P_{3}}\) & \(\mathbf{P_{(at\ 300\ K)}}\) \\ \hline \multirow{4}{*}{**SUS304**} & **E (Pa)** & 0 & \(201.04\times 10^{9}\) & \(3.079\times 10^{-4}\) & \(-6.534\times 10^{-7}\) & 0 & \(207.877\times 10^{9}\) \\  & \(\
u\) & 0 & \(0.3262\) & \(-2.002\times 10^{-4}\) & \(3.797\times 10^{-7}\) & 0 & \(0.3178\) \\ \cline{1-1}  & \(\rho\)(kg/m\({}^{3}\)) & 0 & 8166 & 0 & 0 & 0 & \(8166\) \\ \cline{1-1}  & \(\alpha\)(K\({}^{-1}\)) & 0 & \(12.33\times 10^{-6}\) & \(8.086\times 10^{-4}\) & 0 & 0 & \(15.321\times 10^{-6}\) \\ \cline{1-1}  & \(\kappa\)(Wm/K) & 0 & 12.04 & 0 & 0 & 0 & \(12.04\) \\ \hline \hline \end{tabular}
\end{table}
Table 4: Elasticity modulus (_E_), mass per density (\(\rho\)), coefficient of thermal expansion (\(\alpha\)) and thermal conductivity (\(\kappa\)) of Steel (SUS 304) depending on temperature effect [46].  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Case No**} & \multicolumn{3}{c}{**Modulus of Elasticity (GPa)**} & \multicolumn{1}{c}{**Functionally Grading**} \\ \cline{2-5}  & _Metal I_ & _Metal II_ & _HAZ_ & \
\begin{tabular}{c} **Type** \\ _(HAZ ratio-\(\gamma\))_ \\ \end{tabular} &
\begin{tabular}{c} **Function Equation** \\ \end{tabular} \\ \hline
**(a)** & 201 & 201 & 181 & Exponential (\(\gamma\)=_181/201_) & \(\frac{E_{HAZ}}{p}\frac{\ln(E_{Bust}\text{ }Mental)-\ln(E_{HAZ})}{p}x\) \\
**(b)** & 201 & 201 & 195 & Linear (\(\gamma\)=195/201) & \(\frac{(E_{Bust}\text{ }Mental)-\ln(E_{HAZ})}{p}x+E_{HAZ}\) \\
**(c)** & 201 & 69 & 45 & Linear (\(\gamma\)=45/69) & \(\frac{(E_{Bust}\text{ }Mental)-\ln(E_{HAZ})}{p}x+E_{HAZ}\) \\ \hline \hline \end{tabular}
\end{table}
Table 3: Modulus of elasticity of different functionally graded cases.  
specimen produced by the electric arc welding process is three times the toughness value obtained from the specimen produced by the friction welding process. In addition, the friction welding process is important in that it allows two structures with different properties to be combined. This study can also lead to different studies to follow. In further studies, the electric arc welding process can be compared with other different welding methods and the data obtained as a result of this comparison can be applied to the bending, buckling and vibration characteristic equations of beams, bars and plates. In addition, the mechanical data obtained by performing three-point bending test can be discussed.  
Conceptualization, S.F. and A.N.B.; formal analysis, S.F. and A.N.B.; investigation, A.N.B., S.F. and M.S.; methodology, S.F. and A.N.B.; resources, A.N.B., S.F. and M.S.; validation, A.N.B., S.F. and M.S.; writing--original draft, A.N.B. and S.F.; writing--review and editing, A.N.B. and S.F. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
In this study, the data were obtained as a result of tests performed in the Istanbul TeknoLAB firm and Tekirdag Namik Kemal University NABILTEM laboratories. In addition, FreeCAD 0.18 program and Microsoft Word were used in the drawings.  
The author declares no conflict of interest.