Effects of Process Control Agent Amount, Milling Time, and Annealing Heat Treatment on the Microstructure of AlCrCuFeNi High-Entropy Alloy Synthesized through Mechanical Alloying

Abstract

This study was conducted to investigate the characteristics of the AlCrCuFeNi high-entropy alloy (HEA) synthesized through mechanical alloying (MA). In addition, effects of Process Control Agent (PCA) amount and milling time were investigated using X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). The results indicated that the synthesized AlCrCuFeNi alloy is a dual phase (FCC + BCC) HEA and the formation of the phases is strongly affected by the PCA amount. A high amount of PCA postponed the alloying process and prevented solid solution formation. Furthermore, with an increase in the PCA amount, lattice strain decreased, crystallite size increased, and the morphology of the mechanically alloyed particles changed from spherical to a plate-like shape. Additionally, investigation of thermal properties and annealing behavior at different temperatures revealed no phase transformation up to 400 °C; however, the amount of the phases changed. By increasing the temperature to 600 °C, a sigma phase (σ) and a B2-ordered solid solution formed; moreover, at 800 °C, the FCC phase decomposed into two different FCC phases.

A Quantitative Investigation of Dislocation Density in an Al Matrix Composite Produced by a Combination of Micro-/Macro-Rolling

“…The average of misorientation inside an Al/CNT particle could be between the misorientation of a low angle grain boundary (LAGB) to a high angle grain boundary (HAGB). During the milling process, formation of new dislocations led to increase in the LAGBs in the primary stages, and then, by increase in milling time the LAGBs decreases due to the rearrangement of dislocations as a result of dynamic recovery [29,37,66]. It worth mentioning that, the extension of the LAGBs in the Al alloys remains almost the same at strain larger than 1-2 [67].…”

Fabrication and Characterization of Submicron-Scale Bovine Hydroxyapatite: A Top-Down Approach for a Natural Biomaterial

“…This milling method uses no media in the milling treatment of materials. Milling media such as ethanol and other organic solvent are widely used as PCA in the milling method [ 28 , 29 , 30 ]. PCA functions to avoid cold welding and bonding between the powder particles.…”

Development of high entropy alloys (HEAs): Current trends

“…Compared to stearic acid, methanol, PBTC, and cyclohexane, cyclohexane is capable of influencing the nanostructure through mechanical alloying, and one appealing outcome is that it reduces carbon and oxygen production [ 81 ]. For 60 h of milling, increase the weight percentage (1, 2, 3, 4) of stearic acid to cause the morphology to shift from a spherical to a plate-like structure [ 82 ]. Fig.…”