Coupling between electric and magnetic fields enables smart new devices and may find application in

sensor technology and data storage [<span id='cite-1'></span>[[#1|1]]]. Materials showing magneto-electric (ME) coupling

properties combine two or more ferroic characteristics and are known as multiferroics. Since singlephase

materials show an interaction between polarization and magnetization at very low temperatures

and at the best a too small ME coefficient at room temperature, composite materials become

important. These ME composites consist of magnetically and electrically active phases and generate

the ME coupling as a strain-induced product property. It has to be emphasized that for each of the

two phases the ME coupling modulus is zero and the overall ME modulus is generated by the

interaction between both phases. Here we distinguish between the direct and converse ME effect. The

direct effect characterizes magnetically induced polarization, where an applied magnetic field yields

a deformation of the magneto-active phase which is transferred to the electro-active phase. As a

result, a strain-induced polarization in the electric phase is observed. On the other hand, the converse

effect characterizes electrically activated magnetization. Several experiments on composite

multiferroics showed remarkable ME coefficients that are orders of magnitudes higher than those of

single-phase materials [<span id='cite-2'></span>[[#2|2]]]. Due to the significant influence of the microstructure on the ME effect,

we derived a two-scale finite element (FE<sup>2</sup>) homogenization framework, which allows for the

consideration of microscopic morphologies  [<span id='cite-3'></span>[[#3|3]], <span id='cite-4'></span>[[#4|4]]]. A further major influence on the overall ME

properties is the polarization state of the ferroelectric phase. With this in mind, a material model is

implemented that considers the switching behavior of the spontaneous polarization [<span id='cite-5'></span>[[#5|5]]] and enables a

more exact comparison to experimental measurements in [<span id='cite-6'></span>[[#6|6]]].

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{| style="font-size:120%; color: #222222; border: 1px solid darkgray; background: #f3f3f3; table-layout: fixed; width:100%;"

|- style="border-bottom: 1px solid darkgray; text-align: center;"

| Recording of the presentation

|- 

| {{#evt:service=youtube|id=https://youtu.be/tucxagv9tQ0|alignment=center}}

|- style="text-align: center;" 

| Location: Technical University of Catalonia (UPC), Vertex Building. 

|- style="text-align: center;"

| Date: 1 - 3 September 2015, Barcelona, Spain.

|}

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== General Information ==

* Location: Technical University of Catalonia (UPC), Barcelona, Spain.

* Date: 1 - 3 September 2015

* Secretariat: [//www.cimne.com/ CIMNE] Centre Internacional de Metodes Numerics.

​

== External Links ==

* [//congress.cimne.com/complas2015/frontal/default.asp Complas XIII] Official Website of the Conference.

* [//www.cimnemultimediachannel.com/ CIMNE Multimedia Channel]

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==References==

​

<div id="1"></div>

[[#cite-1|[1]]] N.A. Spalding and M. Fiebig, "The renaissance of magnetoelectric multiferroics", Materials Science, <b>309</b>, 391-392 (2005).

<div id="2"></div>

[[#cite-2|[2]]] M. Fiebig, "Revival of the magnetoelectric effect", Journal of Physics D: Applied Physics, <b>38</b>, R123-R152 (2005). 

<div id="3"></div>

[[#cite-3|[3]]] J. Schröder and M.-A. Keip, "Two-scale homogenization of electro-mechanically coupled boundary value problems", Computational Mechanics, <b>50</b>, 229-244 (2012).

<div id="4"></div>

[[#cite-4|[4]]] M. Labusch, M. Etier, D.C. Lupascu, J. Schröder and M.-A Keip, "Product properties of a two-phase magneto-electric composite: Synthesis and numerical modeling", Computational Mechanics, <b>54</b>, 71-83 (2014).

<div id="5"></div>

[[#cite-5|[5]]] S.C. Hwang, C.S. Lynch and R.M. McMeeking, "Ferroelectric/ferroelastic interactions and a polarization switching model", Acta Metall. Mater., <b>43</b>, 2073-2088 (1995).

<div id="6"></div>

[[#cite-6|[6]]] M. Etier, V.V. Shvartsman, Y. Gao, J. Landers, H. Wende and D.C. Lupascu, "Magnetoelectric effect in (0-3) CoFe<sub>2</sub>O<sub>4</sub>-BaTiO<sub>3</sub> (20/80) composite ceramics prepared by the organosol route", Ferroelectrics, <b>448</b>, 77-85 (2013).

​