Magnetoelectric devices and methods of using same

US7298060B2 · kind B2 · utility

Assignee

• The Hong Kong Polytechnic University · CN

Inventors

• Siu Wing Or · Sha Tin, CN
• Helen Lai Wa Chan-Wong · Hong Kong, CN

Key dates

• Filing date: Feb 21, 2007
• Grant date: Nov 20, 2007
• Expiry date: Feb 21, 2027

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10N35/85

Abstract

The operational frequency of existing magnetoelectric materials having metallic or ceramic magnetostrictive materials and ceramic piezoelectric materials may be limited to a few kilohertz due to the presence of eddy-current losses in the metallic magnetostrictive phase. Further, these materials may be difficult to machine and fabricate due to their brittleness. Additionally, it may be difficult to tailor and optimize the properties (i.e., magnetoelectric voltage coefficient αE, etc.) of the devices. This invention provides a magnetoelectric element including at least one set of alternating piezoelectric layers and magnetostrictive composite layers. The magnetostrictive composite layer includes at least one magnetostrictive material dispersed in first concentrated zones within a first polymer matrix, wherein all of the concentrated zones are orientated along a first direction. It is found that the conversion efficiency (i.e., αE) varies in accordance with applied magnetic control field Hcontrol.