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Abstract It is well known that rare earth (RE) based intermetallic compounds reveal various interesting magnetic properties depending on the crystallized structures and the constituent elements, paving the way for potential applications in different fields. Recent progresses regarding magnetic properties and magnetocaloric effect (MCE) in ternary rare earth RE 2 T 2 X (RE = Gd-Tm; T = Cu, Ni, Co; and X = Cd, In, Ga, Sn, Al) intermetallic compounds are reviewed in this paper. Some of them exhibit excellent MCE performances which make them attractive in the field of magnetic refrigeration at low temperature. With the aim of understanding the magnetocaloric characteristics of RE 2 T 2 X compounds, the crystal structure, magnetism and magnetic phase transition are also focused. The origin of the MCE together with the physics behind and the potential application of RE 2 T 2 X compounds are thoroughly considered. Highlights • Magnetic and magnetocaloric properties in RE 2 T2X compounds are reviewed. • The RE 2 T2X compounds show four types of crystallize structures. • Some of them exhibit excellent cryogenic magnetocaloric performances. • The origin of magnetocaloric effect in RE 2 T2X compounds is discussed. [ABSTRACT FROM AUTHOR]

The magnetic properties and magnetic entropy change of amorphousized Tm 60 Co 20 Ni 20 ribbon were systematically studied. The results indicate that the Tm 60 Co 20 Ni 20 amorphous ribbon reveals a second order magnetic transition (paramagnetic to ferromagnetic state) based on the Arrott plots and rescaled magnetic entropy change curves. A large magnetic entropy change is achieved around its Curie temperature of T C ∼6.7 K. Under the magnetic field change (Δ Η ) of 0–5 T, the maximum values of magnetic entropy change (−Δ S M max ) and relative cooling power ( RCP ) are 17.1 J/kg K and 273 J/kg, respectively. In particular, under a relative low Δ Η of 0–2 T, a large magnetic entropy change of 11.8 J/kg K reaches, making it attractive in the field of low-temperature magnetic refrigeration. [ABSTRACT FROM AUTHOR]

We reported the magnetism, magnetic phase transition behavior and magnetocaloric effect of the ternary Dy 2 CuSi 3 and Ho 2 CuSi 3 compounds. A second order magnetic phase transition from a paramagnetic (PM) to ferromagnetic (FM) state around their respective Curie temperatures were confirmed by using the magnetic measurements and rescaled magnetic entropy change curves in both compounds. A large magnetic entropy change was obtained with the absence of thermal and magnetic hysteresis loss in both compounds. The maximal magnetic entropy change (-Δ S M max ) reach 18.3 and 28.3 J/kg K for a magnetic field change of 0–70 kOe in Dy 2 CuSi 3 and Ho 2 CuSi 3 , respectively. The corresponding values of relative cooling power ( RCP ) are evaluated to be 460 J/kg and 627 J/kg, respectively. [ABSTRACT FROM AUTHOR]

The magnetic properties, magnetocaloric effect (MCE) and universal behaviour of ternary Cadmium compounds Gd 2 Cu 2 Cd and Er 2 Cu 2 Cd have been investigated systematically. A second order magnetic phase transition from a paramagnetic to ferromagnetic state is observed for Gd 2 Cu 2 Cd and Er 2 Cu 2 Cd at their own Curie temperatures of T C ∼120 and 36 K, respectively. A large reversible MCE occurs near its own T C for both compounds. The maximum values of magnetic entropy change (−Δ S M max ) are 10.1 and 19.1 J/kg K under a magnetic field change of 0–7 T with no obviously hysteresis loss for Gd 2 Cu 2 Cd and Er 2 Cu 2 Cd, respectively. The corresponding values of refrigerant capacity ( RC ) and relative cooling power ( RCP ) are evaluated to be 386 and 373 J/kg, and to be 525 and 489 J/kg, respectively. The rescaled magnetic entropy change curves collapse onto a single curve for various magnetic fields, further confirming the Gd 2 Cu 2 Cd and Er 2 Cu 2 Cd compounds with the second order phase transition. [ABSTRACT FROM AUTHOR]

The magnetic properties and magnetocaloric effect (MCE) in Dy 2 Cu 2 In compound have been investigated. Dy 2 Cu 2 In undergoes two magnetic phase transitions, a paramagnetic to ferromagnetic (FM) at T C ∼ 49.5 K followed by a spin reorientation (SR) at T SR ∼ 19.5 K. For a magnetic field change of 0–7 T, the maximum values of the magnetic entropy change (−Δ S M max ) are estimated to be 16.5 around T C and 6.7 J/kg K around T SR with a large relative cooling power ( RCP ) value of 617 J/kg. The modified Arrott plots and universal curves of the rescaled Δ S M confirmed that the magnetic phase transitions in Dy 2 Cu 2 In compound belongs the second order phase transitions. The present results may provide some clues to search for new magnetocaloric materials belonging to RE 2 T 2 X system. [ABSTRACT FROM AUTHOR]

The magnetic and magnetocaloric properties in the equiatomic intermetallic compounds of TmZnAl and TmAgAl have been investigated. The compounds undergo a second order magnetic transition from paramagnetic to ferromagnetic state around its own Curie temperatures T C ∼2.8 K and 3.3 K for TmZnAl and TmAgAl, respectively. A considerable reversible magnetocaloric effect (MCE) was observed at low temperature. For a magnetic field change of 7 T, the maximum values of magnetic entropy change (−Δ S M max ) and relative cooling power ( RCP ) are 11.8 J/kg K and 289 J/kg for TmZnAl, respectively, and the corresponding values for TmAgAl are 14.1 J/kg K and 315 J/kg. [ABSTRACT FROM AUTHOR]

Magnetism and magnetocaloric effect in RE AgAl ( RE = Er and Ho) intermetallic compounds have been studied. Both compounds undergo a second order magnetic phase transition from paramagnetic to ferromagnetic state. A large reversible magnetocaloric effect was observed around its own Curie temperatures T C ∼ 14 and 18 K for ErAgAl and HoAgAl, respectively. For a field change of 0–7 T, the maximum magnetic entropy change reaches 13.7 and 13.8 J/kg K for RE = Er and Ho, respectively. The corresponding relative cooling powers are evaluated to be 398 and 525 J/kg. [ABSTRACT FROM AUTHOR]

Highlights: [•] Magnetism and magnetocaloric effect in ErNi2−x Fe x B2C were studied. [•] Ni site Fe substitution can reduce the magnetic hysteresis of ErNi2B2C. [•] The origin of MCE and its potential application in ErNi2−x Fe x B2C were discussed. [ABSTRACT FROM AUTHOR]

CsCl-type HoZn undergoes two successive magnetic phase transitions: (i) paramagnetic to ferromagnetic (FM) at T C ∼ 72 K and (ii) a spin reorientation (SR) at T SR ∼ 26 K. Magnetization and modified Arrott plots indicate that HoZn undergoes a second-order magnetic phase transition around T C . The obtained critical exponents have some small deviations from the mean-field theory, indicating a short range or a local magnetic interaction which is properly related to the coexistence of FM and SR transitions at low temperature. Two successive magnetic transitions in HoZn induce one broad pronounced peak together with a shoulder in the temperature dependence of the magnetic entropy change −Δ S M ( T ) curves, resulting in a wide temperature range with a large relative cooling power ( RCP ). For a field change of 0–7 T, the maximum value of −Δ S M is 15.2 J/kg K around T C with a large RCP value of 1124 J/kg. The large reversible magnetocaloric effect (MCE) and RC indicate that HoZn is a good candidate for active magnetic refrigeration. [ABSTRACT FROM AUTHOR]

The magnetic properties and magnetocaloric effect (MCE) in dysprosium zinc binary DyZn compound were studied. The compound reveals a paramagnetic-to-ferromagnetic transition together with a spin reorientation phenomenon at Curie temperatures of T C ∼135 and T SR ∼50 K, respectively. A large reversible MCE was observed in DyZn around T C . For the magnetic field change of 0–7 T, the values of maximum magnetic entropy change (–Δ S M max ), relative cooling power ( RCP ), and refrigerant capacity ( RC ) were 12.2 J/kg K, 895 J/kg, and 672 J/kg, respectively. [ABSTRACT FROM AUTHOR]