2026-04-13T05:59:00Zhttps://recercat.cat/oai/requestoai:recercat.cat:10256/188452024-06-18T11:51:06Zcom_2072_452955com_2072_2054col_2072_453063
RECERCAT
author
Dadda, Karima
author
Alleg, Safia
author
Suñol Martínez, Joan Josep
author
Bessais, Lotfi
author
Hill, El-Kebir
2024-06-18T11:51:06Z
2024-06-18T11:51:06Z
info:eu-repo/date/embargoEnd/2021-07-012020-07-01
http://hdl.handle.net/10256/18845
A detailed investigation of structure, critical behaviour and magnetocaloric properties of Ni50Mn30Sn20 (Sn20) and Ni50Mn30In20 (In20) alloys has been investigated by means of X-ray diffraction and magnetic measurements. Ni50Mn30Sn20 alloy shows a cubic austenite L21 structure and undergoes a second order magnetic transition at a Curie temperature of TAc,1(Sn20)=333 K. However, the Ni50Mn30In20 alloy exhibits a mixture of cubic L21 and B2 austenite structures having Curie temperatures of TAc,2(In20)=285 K and T∗c(In20)=330 K, respectively. The modified Arrott plots, Kouvel-Fisher curves and critical isotherm analysis have been used to estimate the critical exponents (β, γ and δ) around the Curie temperature. For Sn20 alloy, the reliable exponents are consistent with the mean field model, revealing long-range ferromagnetic interactions. Nevertheless, the critical exponents of In20 alloy around 330 K cannot be arranged into any of the universality classes of well-known classical standard models. The maximum entropy change under 5 T of Sn20 (ΔSmaxM=2.43Jkg.K) is slightly higher than that of In20 (ΔSmaxM=2.05Jkg.K). The experimental results of entropy changes are in good agreement with those calculated using Landau theoryThis work has been supported by the DGRSDT/MESRS Algeria, PHC-Maghreb 15 MAG07, Spanish MINECO projects MAT2013-47231-C2-2-P and MAT2016-75967-P, and the Erasmus+k107 STA program
Tots els drets reservats info:eu-repo/semantics/openAccess
Metalls -- Aliatges
Metals -- Alloys
Raigs X -- Difracció
X-rays -- Diffraction
Aliatges
Alloys
Aliatges amb memòria de forma
Shape memory alloys
Structure, Magnetocaloric Effect and Critical Behaviour in Ni 50 Mn 30 (Sn, In) 20 Heusler Alloys
info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion peer-reviewed