## 3 Results and Discussion
\begin{table}
\begin{tabular}{c c c c c c c c} \hline  & **Al** & **Fe** & **Ti** & **Ni** & **Cu** & **Mn** & **Y** & **Ce** \\ \hline Al & - & 13 [\%] & 2.7 [\%] & 12.5 [\%] & 10 [\%] & 5.5 [\%] & 21.4 [\%] & 21.8 [\%] \\ Fe & \(-\)11 & - & 15.6 [\%] & 0.8 [\%] & 3.1 [\%] & 8.1 [\%] & 31.8 [\%] & 32.2 [\%] \\ Ti & \(-\)30 & \(-\)17 & - & 14.9 [\%] & 12.9 [\%] & 8.1 [\%] & 19.2 [\%] & 19.6 [\%] \\  & [K/mole] & [K/mole] & \(-\)35 & - & 2.3 [\%] & 7.4 [\%] & 31.3 [\%] & 31.6 [\%] \\ Ni & \(-\)1 & +13 & \(-\)8 & \(-\)8 & - & +5.1 [\%] & 29.6 [\%] & 30 [\%] \\ Cu & \([\)J/mole] & [K/mole] & \([\)J/mole] & \([\)J/mole] & \(+\)4 & - & 25.8 [\%] & 26 [\%] \\ Mn & \(-\)19 & 0 & \(-\)8 [K/mole] & \(-\)8 [K/mole] & \(-\)8 [K/mole] & \([\)k/mole] & - & 25.8 [\%] & 26 [\%] \\ Y & \(-\)38 & \(-\)1 [k/mole] & +15 & \(-\)31 & \(-\)22 & \(-\)1 [k/mole] & - & 0.5 [\%] \\  & [K/mole] & \(-\)1 [k/mole] & [K/mole] & [k/mole] & [k/mole] & \(-\)1 [k/mole] & 0 & - \\ Ce & \(-\)38 & +3 [k/mole] & +18 & \(-\)28 & \(-\)21 & +1 [k/mole] & \([\)k/mole] & - \\  & [K/mole] & [K/mole] & [K/mole] & [k/mole] & [k/mole] & \([\)k/mole] & & \\ \hline \end{tabular}
\end{table} 
Table 1: Atomic radii mismatch (in %) and enthalpies of mixing (in kJ/mole) for Al, Fe, Ni, Ti, and Y binary systems [47]. balls, and jar. After milling for 5 h, the powder particles assume a layered structure, and the particle size of the milled powders is about 10-15 \(\upmu\)m. The powder particles of Al82 Fe16 Ce2 decrease gradually with increasing milling time from 10 to 40 h. This means the fracture process is dominant during the process of the mechanical alloying of the Al82 Fe16 Ce2 alloy powders. The particle size decreased to 1-3 \(\upmu\)m, and some particle agglomerations can be seen in Figure 3g,h). The SEM images of the amorphous Al84 Fe16 (without Ce) and Al82 Fe16Y2 (substitute 2 at.% of Y for Al) alloys' MA for 100 h [39] show that the particle powders of the amorphous alloy are about 10 \(\upmu\)m, which is much higher than that of the Al82 Fe16 Ce2 alloy powders. This means that the addition or substitution of Ce for Al in the Al84 Fe16 alloys or Y in Al82 Fe16Y2, respectively, results in decreasing powder particles. In addition, [PERSON] et al. reported that Ce addition to aluminum alloys contributed to grain refinement [49]. This is achieved by lowering the recalescence temperature and the growth temperature of the Al-Fe eutectic structure, improving the morphology and distribution of the Fe-containing phase. Such enhancements also aid in the consolidation of amorphous powder, facilitating the formation of bulk materials. In the Al82 Fe14 Mn2 Ce2 alloy, amorphization occurs similarly to that observed in Al82 Fe16 Ce2 alloy powders. An fcc solid solution phase, along with an Al phase, appears after milling for 5 h. A halo peak, indicating the presence of an amorphous phase, is observed after 20 h of milling (see Figure 4). The amorphization process of the Al82 Fe14 Mn2 Ce2 alloy powders is completed after 40 h.  
The amorphization of Al82 Fe14 Mn2 Ce2 alloy by MA is as fast as Al82 Fe16 Ce2 alloy. A fully amorphous structure in the Al82 Fe14 Mn2 Ce2 alloy is achieved after 40 h of milling. Substituting 2 atomic percent (at.%) of Mn for Fe in the Al82 Fe16 Ce2 alloy does not significantly affect the amorphization process. Similar observations regarding the GFA of melt-spun Al-La-Ni-Fe alloys were reported by [PERSON] et al. [50]. As indicated in Table 1, the mixing enthalpy of the Mn-Fe pair is 0 kJ/mole, with Mn exhibiting atomic size mismatches of 5.5%, 13%, and 26% with Al, Fe, and Ce, respectively. Fe contributes slightly higher atomic radii mismatches compared to Mn. Meanwhile, the Al-Mn pair shows a greater negative mixing enthalpy (\(-\)19 kJ/mole) than the Al-Fe pair (\(-\)11 kJ/mole). Consequently, the Al82 Fe16 Ce2 alloy exhibits a GFA similar to that of the Al82 Fe14 Mn2 Ce2 alloy. The substitution of Mn for Fe in Al-Fe-Ce alloy results in an unenhanced amorphization process.