Dpto. de Fís. Mater., UPV/EHU, San Sebastián, 20018, Spain.
Dpto. de Física Aplicada, EUPDS, UPV/EHU, 20018, San Sebastian, Spain.
Sci Rep. 2018 Jan 12;8(1):621. doi: 10.1038/s41598-017-19032-z.
We have studied magnetic and structural properties of the Heusler-type Ni-Mn-Ga glass-coated microwires prepared by Tailor-Ulitovsky technique. As-prepared sample presents magnetoresistance effect and considerable dependence of magnetization curves (particularly magnetization values) on magnetic field attributed to the magnetic and atomic disorder. Annealing strongly affects the temperature dependence of magnetization and Curie temperature of microwires. After annealing of the microwires at 973 K, the Curie temperature was enhanced to about 280 K which is beneficial for the magnetic solid state refrigeration. The observed hysteretic anomalies on the temperature dependences of resistance and magnetization in the as-prepared and annealed samples are produced by the martensitic transformation. The magnetoresistance and magnetocaloric effects have been investigated to illustrate a potential technological capability of studied microwires.
我们研究了通过 Tailor-Ulitovsky 技术制备的 Heusler 型 Ni-Mn-Ga 玻璃涂层微丝的磁性和结构性能。所制备的样品表现出磁电阻效应和磁化曲线（特别是磁化值）对磁场的显著依赖性，这归因于磁性和原子无序。退火强烈影响微丝的磁化和居里温度的温度依赖性。在 973 K 下退火后，居里温度提高到约 280 K，这有利于磁固体制冷。在未退火和退火样品的电阻和磁化温度依赖性上观察到的滞后异常是由马氏体相变产生的。已经研究了磁电阻和磁热效应，以说明所研究微丝的潜在技术能力。
