Affiliation:
1. Universidad del Pais Vasco
2. Taras Shevchenko Kiev University
Abstract
The giant magnetically-induced deformation of ferromagnetic shape memory alloys
results from the magnetic field-induced rearrangement of twinned martensite under the magnetic
field. This deformation is conventionally referred to as the magnetic-field-induced-strain (MFIS).
The MFIS is comparable in value with the spontaneous deformation of crystal lattice during the
martensitic transformation of an alloy. Although the first observations of MFIS were reported more
than 30 years ago, it has got a world-wide interest 20 years later after the creation of the Ni–Mn–Ga
alloy system with its practically important room-temperature martensitic structure and experimental
evidence of the large magnetostriction. The underlying physics as well as necessary and sufficient
conditions for the observation of MFIS are the main focus of this chapter. A magnetostrictive
mechanism of the unusual magnetic and magnetomechanical effects observed in Ni–Mn–Ga alloys
is substantiated and a framework of consistent theory of these effects is outlined starting from the
fundamental conception of magnetoelasticity and the commonly known principles of
ferromagnetism and linear elasticity theories. A reasonable agreement between the theoretical
deductions and available experimental data is demonstrated and, in this way, a key role of
magnetoelastic coupling in the magnetomechanical behavior of Ni–Mn–Ga alloys is proved. A
correspondence of magnetostrictive mechanism to the crystallographic features of MFIS and the
basic relationships of the thermodynamics of solids are discussed.
Publisher
Trans Tech Publications, Ltd.
Subject
Mechanical Engineering,Mechanics of Materials,Condensed Matter Physics,General Materials Science
Cited by
66 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献