STUDY OF THE MICROSTRUCTURAL BEHAVIOR AND EFFECT OF ADDING ALUMINUM FOR HIGH ENTROPY OF ALCRCOCUFENI ALLOY : CRITICAL REVIEW

• Main Author: Setiyawan, Arul
• Format: Final Project
• Language: Indonesia
• Subjects: Metalurgi
• Online Access: https://digilib.itb.ac.id/gdl/view/51473
• Institution: Institut Teknologi Bandung

Nowadays, the various kinds of metal alloys have been made for some needs because of its various properties by adding some elements to increase its properties and characteristics required. High entropy alloy is alloy that has high mixing entropy when compared to conventional metal alloys. This alloy has many advantages because it has simple solid solution as strengthening phase so that at high temperatur, it can be stronger than the intermetallic phase. Moreover, the high entropy alloy’s fabrication process are not really require some difficult equipments and techniques so that massive production can be easily implemented with existing equipments. Research source collection was carried out with some papers and jurnals that related to high entropy alloy, AlCoCrFeNi high entropy alloy, the synthesis process, and its microsctructure by adding some aluminium for that alloy. Prior to the critical review, the problem was formulated named microstructure behaviour and effect of adding aluminium for high entropy of AlCrCoCuFeNi alloy and mechanical properties of its alloy. Then an analysis was carried out in the form of discussion regarding the formulation of the problem with the data that has been collected such as XRD and TEM image results, microstructure present, Vickers hardness data to take the hardness value, valence electron concentration (VEC) of each atoms, and the average density of atom to see their tendency to form a phase. By using a critical review, from various research sources, the results of the review shows that the microstructural behaviour of the AlCrCoCuFeNi high entropy alloy is the appearance of the FCC and BCC phases which depend on the addition of aluminium. The addition of aluminium is 0 to 0,5%, the FCC phase was obtained, then the addition of aluminium above 3%, the BCC phase was obtained because of lattice distortion due to addition of Al which has lighter average atomik density. The hardness value increases with the addition of aluminium from 133 HV for x = 0 – 0,5 to 655 HV for x = 3 because Al forms strong bonds with other elements according to the enthalpy of mixing.