Magnetocaloric effect in textured rare earth intermetallic compound ErNi

Abstract

Melt-spun ErNi crystallizes in orthorhombic FeB-type structure (Space group Pnma, no. 62) similar to the arc-melted ErNi compound. Room temperature X-ray diffraction (XRD) experiments reveal the presence of texture and preferred crystal orientation in the melt-spun ErNi. The XRD data obtained from the free surface of the melt-spun ErNi show large intensity enhancement for (1 0 2) Bragg reflection. The scanning electron microscopy image of the free surface depicts a granular microstructure with grains of ∼1 μm size. The arc-melted and the melt-spun ErNi compounds order ferromagnetically at 11 K and 10 K (TC) respectively. Field dependent magnetization (M-H) at 2 K shows saturation behaviour and the saturation magnetization value is 7.2 μB/f.u. for the arc-melted ErNi and 7.4 μB/f.u. for the melt-spun ErNi. The isothermal magnetic entropy change (ΔSm) close to TC has been calculated from the M-H data. The maximum isothermal magnetic entropy change, -ΔSmmax, is ∼27 Jkg-1K-1 and ∼24 Jkg-1K-1 for the arc-melted and melt-spun ErNi for 50 kOe field change, near TC. The corresponding relative cooling power values are ∼440 J/kg and ∼432 J/kg respectively. Although a part of ΔSm is lost to crystalline electric field (CEF) effects, the magnetocaloric effect is substantially large at 10 K, thus rendering melt-spun ErNi to be useful in low temperature magnetic refrigeration applications such as helium gas liquefaction.

Magnetocaloric effect in amorphous-crystalline microcircuits PrDyFeCoB

“…In the field of rare-earth alloys Re−T M−B (Rerare-earth metals, T Mtransition metals, Bboron) a considerable amount of research on the magnetocaloric effect has been done on bulk samples [13][14][15][16][17][18][19][20][21][22][23][24][25]. Studies of micro-magnets exhibiting MCE are not so widely presented in the literature.…”

“…Note that the RCP value in Pr 1.3 Nd 0.7 Fe 17 is comparable in value to the data of our experiments, which is explained by the significant width of the entropy peak in the alloys we study. Magnetocaloric parameters of rare-earth alloys (Curie temperature T c , maximum change in the magnetic component of entropy − S max , RCP) are collected in the Table according to data [13][14][15][16][17][18][19][20][21][22][23][24][25]. It follows from the data presented that the phase transition temperatures investigated in our and other works are close to room temperature.…”

Design of Dual Purpose Fe‐metallogel for Magnetic Refrigeration and Fabrication of Schottky Barrier Diode

“…[25][26][27][28] The extent of MCE depends on three major metal-specific features: (i) large spin ground state, (ii) the zero orbital momentum and (c) the weak super-exchange interactions. [29][30][31][32][33] Taking cue from this, we envisioned that the cryogenic magnetic cooling behaviour of a Fe 3 + based metallogel with least periodic microstructure perfectly suit the purpose. [34][35][36][37][38] It is noteworthy here that Fe 3 + ion with characteristic 6 S 5/2 ground state term (S = 5/2, L = 0) fulfils two basic prerequisites for effective MCE, viz.…”

“…Among the topical magnetism studies, the magnetocaloric effect (MCE) has drawn a great deal of interest due of their potential application as a magnetic refrigerant material [25–28] . The extent of MCE depends on three major metal‐specific features: (i) large spin ground state, (ii) the zero orbital momentum and (c) the weak super‐exchange interactions [29–33] . Taking cue from this, we envisioned that the cryogenic magnetic cooling behaviour of a Fe 3+ based metallogel with least periodic microstructure perfectly suit the purpose [34–38] .…”

Crystal structure and magnetism of rare earth intermetallic compound Dy0.33Ho0.33Er0.33Ni

“…Rare earth intermetallic compounds with equiatomic composition of heavy rare earths (R) such as Gd, Dy, Ho and Er and nickel are known to exhibit large magnetocaloric effect near their ferromagnetic ordering temperature [1,2,3]. In an effort to tailor the magnetic transition temperature and the magnetic entropy change near the transition, rare earth site has been multiply substituted and it was found to be beneficial [4,5].…”