Kustov Sergey, Rosselló Jaume, Corró Miguel Lluís, Kaminskii Vladimir, Sapozhnikov Konstantin, Sozinov Andrey, Sozinov Aleksei, Ullakko Kari
Departament de Física; Universitat de les Illes Balears, Palma de Mallorca 07122, Spain.
Faculty of Laser Photonics and Optoelectronics; ITMO University, 197101 St. Petersburg, Russia.
Materials (Basel). 2019 Jan 25;12(3):376. doi: 10.3390/ma12030376.
The temperature and field dependences of internal friction and Young´s modulus are studied using a high-resolution ultrasonic (90 kHz) technique in stoichiometric ferromagnetic Ni₂MnGa shape memory alloy close to the premartensitic transformation temperature, , in the demagnetized state and under moderate fields. Several new effects observed like an apparent Young´s modulus softening close to under moderate fields, instead of the hardening outside this range, as well as existing controversies in the apparent elastic and anelastic properties of Ni₂MnGa close to are explained by microeddy and macroeddy current relaxations that to date have been disregarded.
在接近马氏体相变前温度、处于退磁状态且在中等磁场下，使用高分辨率超声波（90kHz）技术研究了化学计量比的铁磁Ni₂MnGa形状记忆合金的内耗和杨氏模量与温度及磁场的关系。观察到了几个新效应，如在中等磁场下接近[具体温度]时杨氏模量明显软化，而在此范围之外则是硬化，以及Ni₂MnGa在接近[具体温度]时表观弹性和滞弹性性能方面存在的争议，这些都可以通过迄今为止被忽视的微涡电流和宏涡电流弛豫来解释。
