Ferromagnetic morphotropic phase boundary and magnetostrictive effect of laves phase rare-earth alloys

Magnetostrictive materials are important magnetic functional materials that are widely used in transducers and sensors. Previously, large piezoelectricity was obtained via controlling the composition of ferroelectric materials around morphotropic phase boundary (MPB). Based on the physical parallelism between ferroelectrics and ferromagnetism, it is expected of anomalous field-induced strain effect for magentic materials at MPB. In this article, three types of recently reported ferromagnetic MPB systems are reviewed, and the relationships between various properties and MPB are summarized, not all three types of ferromagnetic MPB systems show large magnetostriction under magnetic field, like ferroelectric MPB systems process large piezoelectricity. The different structures and mechanisms of ferromagnetic MPB systems need to be further studied.