TY - JOUR
T1 - Broad First-Order Magnetic Entropy Change Curve in Directionally Solidified Polycrystalline Ni-Co-Mn-In
AU - Chen, F.
AU - Tong, Y. X.
AU - Li, L.
AU - Sánchez Llamazares, J. L.
AU - Sánchez-Valdés, C. F.
AU - Müllner, P.
N1 - Publisher Copyright:
© 2017 Elsevier B.V.
PY - 2017/12/15
Y1 - 2017/12/15
N2 - We present the thermal dependence of the magnetic entropy change ΔSM(T) across the martensitic transformation for a polycrystalline sample, which was cut from a directionally solidified rod, with a nominal composition Ni42Co8Mn38In12 grown by the Bridgman-Stockbarger technique. This material combines a first-order martensitic transformation expanded over a very large working temperature range with a large magnetization change of ∼86 A m2 kg−1. Accordingly, for a magnetic field change of 5 T (2 T), the coupled magneto-structural transition gives rise to a broad magnetic entropy change curve across the reverse martensitic transformation with a moderate maximum value of 6.8 (3.0) J kg−1 K−1 and a full-width at half-maximum δTFWHM for the ΔSM(T) curve of 49 (43) K. Such a broad structural transition may be due to the effect of chemical segregation introduced by the directional solidification which can be enhanced by the non-uniform distribution of second phase particles. Accompanying with such a wide working temperature range, a large refrigerant capacity of 334 J kg−1 was obtained for a field change of 5 T.
AB - We present the thermal dependence of the magnetic entropy change ΔSM(T) across the martensitic transformation for a polycrystalline sample, which was cut from a directionally solidified rod, with a nominal composition Ni42Co8Mn38In12 grown by the Bridgman-Stockbarger technique. This material combines a first-order martensitic transformation expanded over a very large working temperature range with a large magnetization change of ∼86 A m2 kg−1. Accordingly, for a magnetic field change of 5 T (2 T), the coupled magneto-structural transition gives rise to a broad magnetic entropy change curve across the reverse martensitic transformation with a moderate maximum value of 6.8 (3.0) J kg−1 K−1 and a full-width at half-maximum δTFWHM for the ΔSM(T) curve of 49 (43) K. Such a broad structural transition may be due to the effect of chemical segregation introduced by the directional solidification which can be enhanced by the non-uniform distribution of second phase particles. Accompanying with such a wide working temperature range, a large refrigerant capacity of 334 J kg−1 was obtained for a field change of 5 T.
KW - Broad martensitic transformation
KW - Ferromagnetic shape memory alloy
KW - Magnetocaloric properties
KW - Ni-Co-Mn-In
KW - Working temperature range
UR - http://www.scopus.com/inward/record.url?scp=85028071049&partnerID=8YFLogxK
UR - https://scholarworks.boisestate.edu/mse_facpubs/308
U2 - 10.1016/j.jallcom.2017.08.118
DO - 10.1016/j.jallcom.2017.08.118
M3 - Article
SN - 0925-8388
VL - 727
SP - 603
EP - 609
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
ER -