## 3 Results
### Microhardness  
The aggregation of HEA phases at grain junctions, frequently observed in earlier B4C composite microhardness studies, was responsible for the identification of a porous microstructure and various fissures on the SEM images, primarily along the grain borders [47; 48; 49]. This suggested the need to perform a microhardness statistical analysis. In order to perform this analysis, a fixed load of 19.61 N was applied on numerous occasions along different regions of the surface of all studied samples. With the use of a diamond point pyramidal indenter (136\({}^{\circ}\) edge angle), an indentation was developed after applying a vertical load for 15 s. The hardness of all studied samples as a relation between the applied load and the indentation mark was determined using the Vickers method. Table 3 provides a summary of the findings of all studied samples, accompanied by different visual representations (boxplots, histograms and normal distribution curves) to provide a comprehensive comparison of hardness values across the different composites. In the analysis of the statistical values, it can be seen how 2% and 3% HEA samples exhibit the greatest hardness values, which confirms that HEA doping positively influences the hardness of B4C ceramics. Lower HEA concentrations (0.5% and 1%) showed lower hardness values. This relation can be explained with the microstructure analysis seen in the SEM images, where the porosity of the lower HEA concentration composites was not completely filled, leading to an incomplete phase integration with the ceramic matrix and microstructural inconsistencies. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Parameters**} & **Monolithic** & **0.5\% HEA** & **1\% HEA** & **2\% HEA** & **3\% HEA** \\  & **B4C** & **B4C** & **B4C** & **B4C** & **B4C** \\ \hline Y\({}_{1}\) (S-s\({}^{n}\)/cm\({}^{2}\)) & 4.472 \(\times\) 10\({}^{-8}\) & 5.218 \(\times\) 10\({}^{-5}\) & 4.927 \(\times\) 10\({}^{-5}\) & 8.268 \(\times\) 10\({}^{-9}\) & 1.001 \(\times\) 10\({}^{-8}\) \\ n1 & 0.876 & 0.460 & 0.516 & 0.940 & 0.856 \\ R\({}_{1}\) (ohm\(\cdot\)cm\({}^{2}\)) & 147.3 & 120.4 & 115.1 & 226.9 & 378.6 \\ Y\({}_{2}\) (S-s\({}^{n}\)/cm\({}^{2}\)) & 2.302 \(\times\) 10\({}^{-14}\) & 1.200 \(\times\) 10\({}^{-4}\) & 2.617 \(\times\) 10\({}^{-5}\) & 5.700 \(\times\) 10\({}^{-7}\) & 1.226 \(\times\) 10\({}^{-7}\) \\ n2 & 0.999 & 0.772 & 0.968 & 0.797 & 0.968 \\ R\({}_{2}\) (ohm\(\cdot\)cm\({}^{2}\)) & 2.635 \(\times\) 10\({}^{-3}\) & 13.910 & 1.398 & 317.2 & 209.8 \\ Y\({}_{3}\) (S-s\({}^{n}\)/cm\({}^{2}\)) & 3.284 \(\times\) 10\({}^{-5}\) & 1.972 \(\times\) 10\({}^{-5}\) & 8.002 \(\times\) 10\({}^{-6}\) & 2.118 \(\times\) 10\({}^{-5}\) & 2.061 \(\times\) 10\({}^{-5}\) \\ n3 & 0.8 & 0.948 & 0.987 & 0.889 & 0.894 \\ R\({}_{3}\) (ohm\(\cdot\)cm\({}^{2}\)) & 3.397 & 7.797 & 204.2 & 4.918 & 6.363 \\ Y\({}_{W}\) (S-s\({}^{5}\)/cm\({}^{2}\)) & 2.916 \(\times\) 10\({}^{-4}\) & 1.179 \(\times\) 10\({}^{-3}\) & 1.095 \(\times\) 10\({}^{-4}\) & 8.396 \(\times\) 10\({}^{-5}\) & 8.952 \(\times\) 10\({}^{-6}\) \\ Chi-square & 9.92 \(\times\) 10\({}^{-4}\) & 7.75 \(\times\) 10\({}^{-4}\) & 7.02 \(\times\) 10\({}^{-4}\) & 5.18 \(\times\) 10\({}^{-4}\) & 1.22 \(\times\) 10\({}^{-4}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 2: R(Q(R(QR)Q(RW))) equivalent-circuit parameters for all B4C-doped samples under study. The histogram provides a visual representation of the frequency distribution of Vickers hardness values for each B4C sample under study. This allows for an easy and intuitive comparison of the hardness variations among different compositions. By analyzing the histograms, it is possible to identify the spread, central tendency and asymmetries of the hardness distributions among HEA additions (see Figure 9).