Giant caloric effect of low-hysteresis metamagnetic shape memory alloys with exceptional cyclic functionality

The influence of texture on the reversible elastocaloric effect of a polycrystalline Ni50Mn32In16Cr2 alloy

“…The influence of texture on the reversible elastocaloric effect of a polycrystalline Ni 50 Mn 32 In 16 Cr 2 alloy Fernando Hern andez-Navarro, 1 Juan-Pablo Camarillo-Garcia, 1,a) Christian-Omar Aguilar-Ortiz, 1 Horacio Flores-Z uñiga, 1 David R ıos, 1 Jos e-Gonzalo Gonz alez, 2 and Pablo Alvarez-Alonso 3 We have studied the correlation between the elastocaloric effect and the crystallographic direction where a uniaxial stress is applied in a textured polycrystalline Ni-Mn-In-Cr ferromagnetic shape memory alloy; this alloy displays martensitic transformation around room temperature and presents an L2 1 cubic structure in the austenite phase. The texture in the material was induced by simple arc melting synthesis; using inverse pole figures, a favored grain growth was shown in the direction [001] perpendicular to the cooled surface.…”

Reversible low-field magnetocaloric effect in Ni-Mn-In-based Heusler alloys

“…2(a). Consequently, a T hys of 2.3 K is achieved for the sample with x = 0.3, which is extremely small in comparison with other Ni-Mn-X-based Heusler alloys [12][13][14][15][16][20][21][22][23][24][25][26][27][28][29][31][32][33][34]. Due to the optimization of the hysteresis, the sample can resist the large migration of T t under thermal cycles.…”

“…For magnetic SMAs, the strong correlation between the hysteresis width and λ 2 has been widely reported in Ni-Mn-X-based Heusler alloys [15,16,27,33,49,55,56]. The determination of λ 2 relies on the crystalline structures of austenite and martensite and their lattice parameters [57].…”

“…From this tensor the eigenvalues are calculated: λ 1 = 0.9476(2), λ 2 = 1.0017 (5), and λ 3 = 1.0395(4) where λ 1 < λ 2 < λ 3 . Compared with other Heusler alloys [15,16,27,33,49,55,56], the sample with x = 0.3 exhibits a smaller value of |1 − λ 2 | = 1.7(5) × 10 −3 , which indicates a good geometric compatibility between the two phases. As a result, a small T hys can be obtained, in agreement with the model prediction.…”

“…Ni-Mn-X based Heusler alloys, in which the lattice structure consists of four interpenetrating fcc sublattices, exhibit a magnetostructural transition (MST) from the ferromagnetic cubic austenite to the weakly magnetic martensite with a lower symmetry [12][13][14][15][16][20][21][22]. Due to the coupling of ferromagnetism and ferroelasticity, multifunctional effects, such * Corresponding authors: J.Liu-7@tudelft.nl; xufeng@njust.edu.cn as caloric effects, magnetostrain effect, and magnetoresistance can be triggered under external stress or magnetic field [12][13][14][15][16][23][24][25][26][27]. From the viewpoint of the MCE, the entropy changes of the lattice and the magnetism mainly contribute to the total entropy change ( S t ) during the martensitic transition [28,29].…”