Effect of Al addition and homogenization treatment on the magnetic properties of CoFeMnNi high-entropy alloy
- PDF / 2,664,585 Bytes
- 14 Pages / 595.276 x 790.866 pts Page_size
- 57 Downloads / 205 Views
Effect of Al addition and homogenization treatment on the magnetic properties of CoFeMnNi high-entropy alloy V. S. Hariharan1, Anirudha Karati2, Tripta Parida3, Rahul John1,4, D. Arvindha Babu5, and B. S. Murty1,* 1
Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai 600036, India Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India 3 Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India 4 Institute for Frontier Materials, Deakin University, Geelong, VIC 3220, Australia 5 Advanced Magnetics Group, Defence Metallurgical Research Laboratory, Defence Research and Development Organization, Hyderabad, India 2
Received: 14 April 2020
ABSTRACT
Accepted: 26 August 2020
The effect of Al addition to CoFeMnNi on the phase evolution and magnetic properties was studied for vacuum arc-melted AlxCoFeMnNi (x = 0, 0.3, 0.7, 1) alloys. These alloys were subsequently homogenized at 1050° C for 50 h and water quenched. The CoFeMnNi and Al0.3CoFeMnNi alloys showed single-phase FCC in as-cast and homogenized conditions. The Al0.7CoFeMnNi alloy showed BCC ? FCC phases in as-cast condition, and the phase fraction of FCC phase increased upon homogenization. The AlCoFeMnNi alloy had B2 phase in as-cast condition and had BCC ? FCC phases after homogenization. Scheil simulation was performed to predict the phase evolution during casting, and calculation of phase diagram (Calphad) approach was used to predict the phase evolution during homogenization. CoFeMnNi alloy was ferromagnetic in as-cast condition, whereas it exhibits spin or cluster glass behaviour after homogenization. The Al0.3CoFeMnNi alloy remained paramagnetic in both as-cast and homogenized condition. In Al0.7CoFeMnNi alloy, the saturation magnetization increased from 20 to 60 emu/g upon homogenization. In the as-cast alloys, AlCoFeMnNi had a maximum saturation magnetization of 126.2 emu/g, and upon homogenization, the saturation magnetization decreased to 94.3 emu/g due to the phase change associated with it. The BCC/B2 phase with equiatomic or near-equiatomic composition had a high saturation magnetization. The change in magnetic properties is correlated to the phase change associated with Al addition and homogenization.
Ó
Springer Science+Business
Media, LLC, part of Springer Nature 2020
Handling Editor: Avinash Dongare.
Address correspondence to E-mail: [email protected]
https://doi.org/10.1007/s10853-020-05171-8
J Mater Sci
Introduction Contrary to the traditional method of alloying that exploits the boundaries of multicomponent phase diagrams, high-entropy alloys (HEAs) focus on the compositions close to the centre of the phase diagram [1]. This opens up a broad compositional space with a wide range of material properties that need to be explored. Till date, the majority of research in HEAs have addressed its applications as potential structural materials which include variation in composition and processing conditions [2]. However, there is a growin
Data Loading...
