# Al-Fe-Ni Metallic Glasses via Mechanical Alloying and Its Consolidation
## 3 Results and Discussion
[41] also reported that the decrease of M\({}_{8}\) is due to chemical composition, the local environment of the magnetic atoms and the electronic structures of the materials. [PERSON] et al. revealed that the M\({}_{8}\) and H\({}_{\rm c}\) of a micro-sized particle are significantly influenced by its structure [42]. For Al\({}_{82}\)Fe\({}_{14}\)Ni\({}_{4}\) alloys, the addition of the ferromagnetic element Ni decreases the content of the ferromagnetic element Fe, as the electronic interaction between Fe-Ni is weaker than Fe-Fe. Therefore, the M\({}_{8}\) of the Al\({}_{82}\)Fe\({}_{14}\)Ni\({}_{4}\) alloy is lower. In addition, the dissolution of  
Figure 4: XRD patterns of Al\({}_{82}\)Fe\({}_{14}\)Ni\({}_{4}\) powders under different milling times at (a) 250 rpm and (b) 350 rpm. the ferromagnetic atoms Fe into the paramagnetic Al-rich phase to produce amorphous phases (40-60 h) lead to a reduction of M\({}_{6}\) (Figure 5). The tendency could similarly be observed for amorphous Ti\({}_{50}\)Fe\({}_{50}\) alloys prepared by MA [41]. The highest H\({}_{\text{c}}\) values (Table 3) of the powders milled at 250 and 350 rpm were approximately 384 and 366.38 Oe after 10 and 5 h of milling, respectively. The increase of coercivity can be found in the Co\({}_{40}\)Fe\({}_{22}\)Ta\({}_{8}\)B\({}_{30}\) alloy produced by MA [43]. It can be explained that the increase of the coercivity was derived from the existence of a high dislocation density and residual stresses in the powders during milling [43; 44; 45; 46]. Two alloy powders were milled at the different speeds had different values of macrostrain, which increased with the milling time. Upon further milling, amorphization started and progressed slowly. As in the Al\({}_{82}\)Fe\({}_{14}\)Ni\({}_{4}\) alloy, this transformation was delayed, and it could be expected that the changes in the coercive force would occur in powders milled at 250 rpm more slowly than in the alloy powder milled at 350 rpm. After milling for 60 h, the coercive force values for powders milled at 250 and 350 rpm were 258.05, and 173.10 Oe, respectively. In this work, Al\({}_{82}\)Fe\({}_{14}\)Ni\({}_{4}\) alloys demonstrated soft magnetic behavior. However, [PERSON] et al. found that the amorphous alloys Al\({}_{86}\)Ni\({}_{5}\)La\({}_{5}\), Al\({}_{86}\)Ni\({}_{9}\)(La\({}_{0.5}\)Ce\({}_{0.5}\))\({}_{5}\) and Al\({}_{86}\)(Ni\({}_{0.5}\)Co\({}_{0.5}\))\({}_{9}\)(La\({}_{0.5}\)Ce\({}_{0.5}\))\({}_{5}\) have diamagnetic properties by using the arc-melting method [47]. In order to study the thermal stability of amorphous Al\({}_{82}\)Fe\({}_{14}\)Ni\({}_{4}\) alloys, the powders were crystallized in the DSC measurements by continuous heating at a rate of 20 K/min. There are two exothermic crystallization peaks observable for the amorphous alloy powders milled at 250 and 350 rpm (Figure 6) for 60 h. Each exothermic crystallization peak can be characterized by its onset (T\({}_{\text{x}}\)) and peak (T\({}_{\text{p}}\)) temperatures. Amorphous alloy powders milled at the speed of 350 rpm have higher T\({}_{\text{x}}\) than the that at 250 rpm. For the first exothermal peak, the T\({}_{\text{x1}}\) of the alloy powders milled at 250 and 350 rpm were 341 and  
Figure 5: Hysteresis curves of the powders milled for 5, 10, 20, 40 and 60 h (**a**) at 250 rpm and (**b**) at 350 rpm. 377 \({}^{\circ}\)C, respectively. The second peak corresponds to the transformation of the residual amorphous alloy to intermetallic compounds, with T\({}_{\text{x2}}\) and T\({}_{\text{p2}}\) temperatures of 537 \({}^{\circ}\)C and 570 \({}^{\circ}\)C (milled at 250 rpm) and 531 \({}^{\circ}\)C and 581 \({}^{\circ}\)C (milled at 350 rpm), respectively.