## 5 Result and Discussion
### Numerical Simulation of Thermal Shock Resistance
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**No.**} & **Factor A** & **Factor B (Coating Thickness)** & **Factor C (Fiber Content)** & **Mean SDEG** \\  & **(Porosity)** & **(Chickness)** & **Content)** & **Value** \\ \hline
1 & 1 & 1 & 0.7847 \\ \hline
2 & 1 & 2 & 3 & 0.3929 \\ \hline
3 & 1 & 3 & 2 & 0.3320 \\ \hline
4 & 2 & 1 & 3 & 0.4031 \\ \hline
5 & 2 & 2 & 2 & 0.4399 \\ \hline
6 & 2 & 3 & 1 & 0.7153 \\ \hline
7 & 3 & 1 & 2 & 0.2518 \\ \hline
8 & 3 & 2 & 1 & 0.7259 \\ \hline
9 & 3 & 3 & 3 & 0.3854 \\ \hline \multirow{2}{*}{Level} & \begin{tabular}{c} Factor A \\ (Porosity) \\ \end{tabular} & \
\begin{tabular}{c} Factor B (Coating Thickness) \\ \end{tabular} &
\begin{tabular}{c} Factor C (Fiber Content) \\ \end{tabular} & \\ \hline K\({}_{1}\) & 1.51 & 1.44 & 2.23 \\ \hline K\({}_{2}\) & 1.56 & 1.56 & 1.02 \\ \hline K\({}_{3}\) & 1.36 & 1.43 & 1.18 \\ \hline k\({}_{1}\) & 0.50 & 0.48 & 0.74 \\ \hline k\({}_{2}\) & 0.52 & 0.52 & 0.34 \\ \hline k\({}_{3}\) & 0.45 & 0.47 & 0.39 \\ \hline R & 0.07 & 0.04 & 0.40 \\ \hline Priority of & & & \\ Factors & & C \textgreater{} A \textgreater{} B & \\ \hline Optimal & & & \\ Configuration & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Orthogonal simulation results and analysis of substrate degradation efficiency (mean SDEG) after the first thermal shock. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**No.** & \begin{tabular}{c} **Factor A** \\ **(Porosity)** \\ \end{tabular} & \begin{tabular}{c} **Factor B (Coating** \\ **Thickness)** \\ \end{tabular} & \
\begin{tabular}{c} **Factor C (Fiber** \\ **Content)** \\ \end{tabular} &
\begin{tabular}{c} **Mean SDEG** \\ **Value** \\ \end{tabular} \\ \hline
1 & 1 & 1 & 1 & 0.8856 \\ \hline
2 & 1 & 2 & 3 & 0.4555 \\ \hline
3 & 1 & 3 & 2 & 0.5076 \\ \hline
4 & 2 & 1 & 3 & 0.4982 \\ \hline
5 & 2 & 2 & 2 & 0.5952 \\ \hline
6 & 2 & 3 & 1 & 0.8797 \\ \hline
7 & 3 & 1 & 2 & 0.5335 \\ \hline
8 & 3 & 2 & 1 & 0.8915 \\ \hline
9 & 3 & 3 & 3 & 0.4629 \\ \hline \multirow{2}{*}{Level} & \begin{tabular}{c} Factor A \\ **(Porosity)** \\ \end{tabular} & \begin{tabular}{c} Factor B (Coating \\ **Thickness)** \\ \end{tabular} & \begin{tabular}{c} Factor C (Fiber \\ **Content)** \\ \end{tabular} & \\ \hline K\({}_{1}\) & 1.85 & 1.92 & 2.66 \\ \hline K\({}_{2}\) & 1.97 & 1.94 & 1.64 \\ \hline K\({}_{3}\) & 1.89 & 1.85 & 1.42 \\ \hline k\({}_{1}\) & 0.62 & 0.64 & 0.89 \\ \hline k\({}_{2}\) & 0.66 & 0.65 & 0.55 \\ \hline k\({}_{3}\) & 0.63 & 0.62 & 0.47 \\ \hline R & 0.04 & 0.03 & 0.41 \\ \hline \
\begin{tabular}{c} Priority of \\ **Factors** \\ \end{tabular} &
\begin{tabular}{c} C \textgreater{} A \textgreater{} B \\ **(**no Porosity, 100 \(\upmu\)m Thickness, and 60\% Fiber** \\ **Content)** \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 10: Orthogonal simulation results and analysis of substrate degradation efficiency (mean SDEG) after the second thermal shock. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**No. ** & \begin{tabular}{c} **Factor A** \\ **(Porosity)** \\ \end{tabular}  & \begin{tabular}{c} **Factor B** \\ **(Coating** \\ **Thickness)** \\ \end{tabular}  & \ \begin{tabular}{c} **Factor C (Fiber** \\ **Content)** \\ \end{tabular}  & \begin{tabular}{c} **Mean SDEG** \\ **Value** \\ \end{tabular}  \\ \hline
1 & 1 & 1 & 1 & 0.8856 \\ \hline
2 & 1 & 2 & 3 & 0.4605 \\ \hline
3 & 1 & 3 & 2 & 0.5166 \\ \hline
4 & 2 & 1 & 3 & 0.5005 \\ \hline
5 & 2 & 2 & 2 & 0.5963 \\ \hline
6 & 2 & 3 & 1 & 0.8799 \\ \hline
7 & 3 & 1 & 2 & 0.5386 \\ \hline
8 & 3 & 2 &