论文标题
化学和静水压力对Ni-Mn-In Heusler合金的耦合磁结构过渡的影响
Effect of chemical and hydrostatic pressure on the coupled magnetostructural transition of Ni-Mn-In Heusler alloys
论文作者
论文摘要
Ni-Mn-In磁性 - 记忆远程合金通常在其一阶马氏体相变时表现出较大的热滞后，这阻碍了技术在磁制冷中的应用。通过优化ni $ _2 $ cu $ _x $ mn $ _ {1.4-x} $中的CU内容，我们获得了Ni $ _ {2} $ cu $ _ {0.2} $ _ {0.2} $ Mn $ _ $ _的$ _ {1.2 $ _2 $ _2 $ {1.2 $ _2 $ _2 $ _2 $ _2我们可以通过马氏体和奥氏体相的界面上几乎完美的习惯平面来解释这种很小的滞后。静水压力的施用不会进一步降低滞后，而是会将马氏体过渡转移到室温附近。等温熵变化不取决于变暖或冷却方案，并且与压力无关。 Ni $ _ {2} $ cu $ _ {0.2} $ Mn $ _ {1.2} $ in $ _ {0.6} $中的脉冲磁场实验，$ 13k。
Ni-Mn-In magnetic shape-memory Heusler alloys exhibit generally a large thermal hysteresis at their first-order martensitic phase transition which hinder a technological application in magnetic refrigeration. By optimizing the Cu content in Ni$_2$Cu$_x$Mn$_{1.4-x}$In$_{0.6}$, we obtained a thermal hysteresis of the martensitic phase transition in Ni$_{2}$Cu$_{0.2}$Mn$_{1.2}$In$_{0.6}$ of only 6 K. We can explain this very small hysteresis by an almost perfect habit plane at the interface of martensite and austenite phases. Application of hydrostatic pressure does not reduce the hysteresis further, but shifts the martensitic transition close to room temperature. The isothermal entropy change does not depend on warming or cooling protocols and is pressure independent. Experiments in pulsed-magnetic fields on Ni$_{2}$Cu$_{0.2}$Mn$_{1.2}$In$_{0.6}$ find a reversible magnetocaloric effect with a maximum adiabatic temperature change of -13 K.
