TY - JOUR
T1 - Drastic Influence of Synthesis Conditions on Structural, Magnetic, and Magnetocaloric Properties of Mn(Fe,Ni)(Si,Al) Compounds
AU - Nuendute, Balnude
AU - Hanggai, Wuliji
AU - Yibole, Hargen
AU - Tana, Bao
AU - Tegus, Ojiyed
AU - Guillou, Francois
PY - 2022
Y1 - 2022
N2 - Mn compounds presenting magneto-structural phase transitions are currently intensively studied for their giant magnetocaloric effect; nevertheless, several parameters remain to be further optimized. Here, we explore the Mn(Fe,Ni)(Si,Al) series, which presents two advantages. The Mn content is fixed to unity ensuring a large saturation magnetization, and it is based on non-critical Si and Al elements instead of the more commonly employed Ge. Structural and magnetic properties of MnFe0.6 Ni0.4 Si1-x Alx compounds are investigated using powder X-ray diffraction, SEM, EDX, DSC, and magnetic measurements. We demonstrate that a magneto-structural coupling leading to transformation from ferromagnetic with orthorhombic TiNiSi-type structure to a paramagnetic hexagonal Ni2 In-type phase can be realized for 0.06 < x ≤ 0.08. Unfortunately, the first-order transition is relatively broad and incomplete, likely as the result of insufficient sample homogeneity. A comparison between samples synthesized in different conditions (as-cast, quenched from 900◦ C, or quenched from 1100◦ C) reveals that Mn(Fe,Ni)(Si,Al) samples decompose into a Mn5 Si3-type phase at intermediate temperatures, preventing the synthesis of high-quality samples by conventional methods such as arc-melting followed by solid-state reaction. By identifying promising MnFe0.6 Ni0.4 Si1-x Alx compositions, this study paves the way toward the realization of a giant magnetocaloric effect in these compounds using alternative synthesis techniques.
AB - Mn compounds presenting magneto-structural phase transitions are currently intensively studied for their giant magnetocaloric effect; nevertheless, several parameters remain to be further optimized. Here, we explore the Mn(Fe,Ni)(Si,Al) series, which presents two advantages. The Mn content is fixed to unity ensuring a large saturation magnetization, and it is based on non-critical Si and Al elements instead of the more commonly employed Ge. Structural and magnetic properties of MnFe0.6 Ni0.4 Si1-x Alx compounds are investigated using powder X-ray diffraction, SEM, EDX, DSC, and magnetic measurements. We demonstrate that a magneto-structural coupling leading to transformation from ferromagnetic with orthorhombic TiNiSi-type structure to a paramagnetic hexagonal Ni2 In-type phase can be realized for 0.06 < x ≤ 0.08. Unfortunately, the first-order transition is relatively broad and incomplete, likely as the result of insufficient sample homogeneity. A comparison between samples synthesized in different conditions (as-cast, quenched from 900◦ C, or quenched from 1100◦ C) reveals that Mn(Fe,Ni)(Si,Al) samples decompose into a Mn5 Si3-type phase at intermediate temperatures, preventing the synthesis of high-quality samples by conventional methods such as arc-melting followed by solid-state reaction. By identifying promising MnFe0.6 Ni0.4 Si1-x Alx compositions, this study paves the way toward the realization of a giant magnetocaloric effect in these compounds using alternative synthesis techniques.
KW - Magnetic properties
KW - Magnetocaloric materials
KW - Manganese compounds
KW - Phase diagram
UR - http://www.scopus.com/inward/record.url?scp=85124389028&partnerID=8YFLogxK
U2 - 10.3390/cryst12020233
DO - 10.3390/cryst12020233
M3 - Article
AN - SCOPUS:85124389028
SN - 2073-4352
VL - 12
JO - Crystals
JF - Crystals
IS - 2
M1 - 233
ER -