Effect of Transition Elements on the Thermal Stability of Glassy Alloys 82Al–16Fe–2TM (TM: Ti, Ni, Cu) Prepared by Mechanical Alloying

Abstract

In the present study, the thermal stability and crystallization behavior of mechanical alloyed metallic glassy Al82Fe16Ti2, Al82Fe16Ni2, and Al82Fe16Cu2 were investigated. The microstructure of the milled powders was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). The results showed remarkable distinction in thermal stability of the alloys by varying only two atomic percentages of transition elements. Among them, Al82Fe16Ti2 alloy shows the highest thermal stability compared to the others. In the crystallization process, exothermal peaks corresponding to precipitation of fcc-Al and intermetallic phases from amorphous matrix were observed.

Enhanced thermal stability of amorphous Al-Fe alloys by addition of Ce and Mn

“…There are two exothermic peaks during the crystallization of these alloys. [13], tends to precipitate easily from Al-Fe amorphous alloys. The presence of alloying elements such as TM and RE, which enhances the thermal stability of the Al 84 Fe 16 -based amorphous alloy, is shown in table 1.…”

“…Furthermore, the amorphous-to-crystalline temperature transformation is induced by thermal annealing strongly depending on the chemical composition of the sample [10,11]. There have been several attempts to improve the thermal stability of Al-Fe amorphous alloys by adding transition elements such as Ti, Ni, or Cu [12,13]. Among these alloys, Al 82 Fe 16 Ti 2 exhibits the highest crystallization onset temperature of 398 °C and higher than that of Al 84 Fe 16 amorphous alloys (T onset = 352.2 °C) [14].…”

Phase Formation of Iron-Based Superconductors during Mechanical Alloying

“…Mechanical activation or mechanical alloying is a solid-state powder processing technique for producing high homogeneity ceramic or metallic materials. The MA process kinetics depends mainly on the milling jar volume, ball-to-powder ratio, and initial size of the material [ 41 , 42 ]. The point of MA is in repeated colliding of the material with balls, flattening, cold welding, grinding and rewelding of the particles during high-energy milling.…”

On the Continuous Mechanics First and Second-Order Formulations for Nonequilibrium Nucleation: Derivation and Applications

“…The surface area 𝐴𝐴(𝑟𝑟 ⃗) depends on the geometry of the nucleating phase as a consequence of thermodynamic variables such as work 𝛔𝛔𝑉𝑉 (pressure, surface tension and volume), composition, temperature, as seen from the pressure vs. temperature phase diagrams obtained from first-principles calculations found in Kapil et al [29] and from the experimental study on the ice crystal formation [30]. The initially derived model by Ferreira [18] could not predict either the decrease in crystal regularity or the crystalline-glassy transition associated with the cooling rate and composition [31,32]. Ferreira et al [19,20], by considering the volumetric and surface entropy relationship, added both effects to the formulation of nucleation,…”