## 3 Results and Discussion  
### Results of the ISO 527-2 Tensile Tests  
The measured stress-strain curves of the tensile test of the ISO 527-2 Type 1A specimens can be seen in Figure 7.  
From the measured characteristics, [PERSON]'s modulus and the yield stress were evaluated. First, the [PERSON]'s modulus was evaluated at the strain interval of 0.05-0.25% recommended by the ISO 527-2 standard [34]. However, the calculated results' maximum deviation from the median value was way more than 5%. To check if it was a measurement error or the material had inconsistencies in that small strain region, the [PERSON]'s modulus was checked between the 0.25% and 0.45% strain values. This strain interval provided significantly better results. The [PERSON]'s modulus values of the five specimens in the two different strain intervals can be seen in Table 1.  
Figure 6: Zones defined for evaluation of the average values.  
Figure 7: Stress-strain curves of the five tensile specimens until failure.  
From Table 1, it can be seen that the smaller interval provided significantly higher standard deviation and maximum difference values. Since the 0.25-0.45% strain interval provided results with less than 5% maximum difference, those values were used in the simulations.  
After evaluating the average Young's modulus, the average yield stress and the average Poisson's ratio were also evaluated for the simulations. These values can be seen in Table 2.  
After evaluating the constants required for the simulations, the elastic behavior of the material was inspected. By fitting a line based on the evaluated [PERSON]'s modulus to each specimen and calculating the relative difference between the measured curve and the fitted line, we were able to determine when the linear elastic region ends. The maximum relative error was defined as 5%. The first strain value where the relative error becomes larger than the defined maximum has been chosen as the end of the linear elastic section. These values can be seen in Table 3.  
From Table 3, it can be seen that the end of the linear elastic region in the material is at a strain value of 0.96%. This strain value is the expected limit of the linear elastic material model's accuracy.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Specimens** & **Young’s Modulus Values at 0.05–0.25\% Strains** & **Young’s Modulus Values at 0.25–0.45\% Strains** \\  & **(MPa)** & **(MPa)** \\ \hline Specim 1 & 1079.000 & 1077.700 \\ Specim 2 & 1261.000 & 1099.900 \\ Specim 3 & 1079.200 & 1100.800 \\ Specim 4 & 1330.300 & 1122.100 \\ Specim 5 & 1362.000 & 1134.800 \\ \hline Average & 1222.300 & 1107.060 \\ Std. deviation & 135.730 & 22.069 \\ \hline Median & 1261.000 & 1100.800 \\ Max. difference & 14.430\% & 3.090\% \\ \hline \hline \end{tabular}
\end{table}
Table 1: Young’s modulus values of the five specimens in the two strain intervals.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Material Constants** & **Average Value** \\ \hline [PERSON]’s modulus (MPa) & 1107.060 \\ Yield stress (MPa) & 39.981 \\ Poisson’s ratio (-) & 0.450 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Measured average material constants required for the simulations.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Specimens** & **End of the Linear Elastic Region (\%)** \\ \hline Specim 1 & 0.976 \\ Specim 2 & 0.956 \\ Specim 3 & 0.926 \\ Specim 4 & 0.995 \\ Specim 5 & 0.961 \\ \hline Average & 0.963 \\ Std. deviation & 0.026 \\ \hline Median & 0.961 \\ Max. difference & 3.69\% \\ \hline \hline \end{tabular}
\end{table}
Table 3: The end of the linear elastic section for each specimen based on a fitted line.