Purpose

This paper aims to investigate the efficiency of a laminated composite for shielding applications. The solution has to be efficient not only for the shield against static magnetic fields but also “for low-frequency ones, in order to be well-suited for applications with electromagnetic perturbations in the frequency range DC to 100 kHz.”

Design/methodology/approach

The composite constituted of a steel sheet taken in a sandwich between two aluminum (Al) sheets is produced by cold roll bonding. A good adherence between Al and steel sheets, ensuring a good mechanical resistance, is obtained with a specific process. A previous study has shown that the optimal trade-off between adherence and magnetic shielding effectiveness (SE_H) is obtained with a 230 µm composite produced with an initial thickness of Al and steel sheets, respectively, of 250 and 100 µm. In this paper, the 230 µm Al/steel/Al composite is used in three applications modelized by two-dimensional numerical simulations. To obtain reasonable computation time for the simulations, a homogenization method is applied to the composite. Studied applications are a cylindrical box containing a coil, a square box under an external magnetic field and a high voltage cable.

Findings

In each application, SE_H is calculated at low frequency and different materials (Al/steel/Al, Al, steel and copper) are compared. It is observed that, in each application, the composite presents higher SE_H at equal mass, especially for frequencies between 5 and 100 kHz.

Originality/value

The proposed approach, from the material point of view to the system consideration, shows that the thin bimetallic composite is an innovative and promising solution for magnetic shielding in the case of applications with both DC and low-frequency perturbations.

中文翻译：

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薄铝/钢/铝复合材料的磁屏蔽

目的

本文旨在研究用于屏蔽应用的层压复合材料的效率。该解决方案不仅必须有效地屏蔽静电磁场，而且还必须“对于低频磁场有效，以使其非常适合直流至100 kHz频率范围内的电磁干扰应用”。

设计/方法/方法

由钢板制成的复合材料被夹在两片铝（Al）板之间，通过冷轧粘合制成。通过特定的工艺可以获得铝和钢板之间的良好附着力，从而确保良好的机械强度。先前的研究已经表明，最佳折衷的粘附性和磁屏蔽效能（SE之间_ħ与230）中获得 μ中号复合材料的Al和钢板的初始厚度产生的250和100分别 μ米。在本文中，230  µm铝/钢/铝复合材料用于二维数值模拟建模的三个应用中。为了获得合理的仿真计算时间，将均质化方法应用于复合材料。研究的应用是一个装有线圈的圆筒形盒子，一个在外部磁场下的方形盒子和一条高压电缆。

发现

在每种应用中，SE _H都是以低频计算的，并且会比较不同的材料（Al /钢/ Al，Al，钢和铜）。可以看出，在每种应用中，复合材料在相同质量下表现出更高的SE _H值，尤其是在5至100 kHz之间的频率下。

创意/价值

从材料的角度到系统的考虑，所提出的方法表明，在同时存在直流和低频扰动的情况下，薄的双金属复合材料是一种新颖且有希望的磁屏蔽解决方案。