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In this study, FeAl2 and Fe2Al5 intermetallic alloys were prepared by conventional casting technique. In order to study their structural stability the alloys were subjected to high-energy ball milling process for 1, 2.5, 5 and 10 h. The structural and chemical characterizations were conducted by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and differential scanning calorimetry. After 10 h of milling, the experimental results indicated a phase transformation from FeAl2-triclinic phase to Fe2Al5-ortorrombic structure. This phase transformation is characterized by a change from low to high symmetry systems.

FeAl3 and FeAl2 intermetallic alloys composition was produced by conventional casting technique. Typically these intermetallic alloys are susceptible to hydrogen environment embrittlement. In this process, water vapor in the air induced cleavage fracture of intermetallic alloys. In order to take advantage of this phenomenon, we evaluate the embrittlement reaction during ball-milling of the pre-alloyed intermetallic material and water under different milling times. During the corrosion reaction, the amount of hydrogen releases was correlated to the amount of aluminum hydroxide formation. The obtained results were based on X-ray diffraction and scanning and transmission electron microscopy. It was observed that as the milling time increased the amount of hydrogen liberated is increased. The intermetallic FeAl3 the 72.95 wt. % reacted with water and the hydrogen release was 0.7769 L and is near the theoretical values that can be obtained.

In this work, we reported the results obtained by the structural characterization of the FeAl3 intermetallic compound. This material was synthesized by conventional casting technique using Fe (99.97%) and Al (99.92%) elemental metals. Then, the as-cast alloy was subjected to high-energy ball-milling for different times (1, 2.5, 5, 7.5, 10 and 15 h). The characterization of the alloy was performed by X-ray diffraction patterns, scanning and transmission electron microscopy. The results show that FeAl3 intermetallic was produced as a single-phase after conventional casting. The milled experiments show that the FeAl3 (monoclinic) transforms to Fe2Al5 (orthorhombic) after 15h of milling. Therefore, this phase transformation is characterized by a change from low to high symmetry systems.

Al based intermetallic materials are commonly susceptible to hydrogen embrittlement reaction. Water vapor in the air reacts with the aluminum in the alloy and releasing hydrogen. Thus, the aid of this work is to know how much hydrogen can be released when the embrittlement reaction is induced inside the milling container. For this purpose the CuAl2intermetallic material was made by conventional castings methods and then subjected to high-energy ball milling in water. The samples were characterized by X-ray diffraction pattern, attenuated total reflectance spectroscopy and scanning electron microscopy (SEM). After the milling process, the amount of hydrogen released was correlated with the other reaction products obtained during the reaction. These products were primarily aluminum hydroxides. The amount of hydrogen that can be released is similar to the theoretical amount possible that can be released.