Jäger Gustav J L, Fischer Lukas, Lutz Tyler, Menzel Andreas M
Institut für Physik, Otto-von-Guericke-Universität Magdeburg, Universitätsplatz 2, 39106 Magdeburg, Germany.
J Phys Condens Matter. 2022 Oct 20;34(48). doi: 10.1088/1361-648X/ac98e8.
Magnetosensitive elastomers respond to external magnetic fields by changing their stiffness and shape. These effects result from interactions among magnetized inclusions that are embedded within an elastic matrix. Strong external magnetic fields induce internal restructuring, for example the formation of chain-like aggregates. However, such reconfigurations affect not only the overall mechanical properties of the elastomers but also the transport through such systems. We concentrate here on the transport of heat, that is thermal conductivity. For flat, thin model systems representing thin films or membranes and modeled by bead-spring discretizations, we evaluate the internal restructuring in response to magnetization of the particles. For each resulting configuration, we evaluate the associated thermal conductivity. We analyze the changes in heat transport as a function of the strength of magnetization, particle number, density of magnetizable particles (at fixed overall particle number), and aspect ratio of the system. We observe that varying any one of these parameters can induce pronounced changes in the bulk thermal conductivity. Our results motivate future experimental and theoretical studies of systems with magnetically tunable thermal but also electric conductivity-both of which have only rarely been addressed so far.
磁敏弹性体通过改变其刚度和形状来响应外部磁场。这些效应源于嵌入弹性基体中的磁化内含物之间的相互作用。强外部磁场会引发内部重构，例如形成链状聚集体。然而，这种重新配置不仅会影响弹性体的整体力学性能，还会影响通过此类系统的传输。我们在此专注于热传输，即热导率。对于代表薄膜或膜且通过珠簧离散化建模的扁平薄模型系统，我们评估粒子磁化引起的内部重构。对于每种最终构型，我们评估相关的热导率。我们分析热传输随磁化强度、粒子数量、可磁化粒子密度（在总粒子数固定时）以及系统纵横比的变化。我们观察到，改变这些参数中的任何一个都可能导致体热导率发生显著变化。我们的结果推动了对具有磁可调热导率和电导率系统的未来实验和理论研究——到目前为止，这两者都很少被涉及。
