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本文介绍了数控机床电磁兼容设计的思想和几种常用的方法,根据数控机床电磁信号干扰源和传播方式,其电磁兼容设计主要采取屏蔽和接地等措施,正确的接地和屏蔽是保证数控机床稳定、可靠运行的重要措施.从电磁兼容的电磁原理出发,分析了电磁辐射、传导耦合和瞬态场等干扰信号的传输和影响途径.屏蔽和接地是抑制干扰的重要方法,正确使用屏蔽和... 相似文献
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对某电磁屏蔽方舱进行设计,从方舱的电磁屏蔽原理入手,对方舱大板间连接处、通风窗、电源接口窗、线孔和推拉门等孔口处进行屏蔽设计,方舱完成后采用双脊波导喇叭天线进行屏蔽效能测试。结果表明:该方舱接口处全部达到了屏蔽指标要求,方舱整体满足60dB的屏蔽效能要求。可为同类型屏蔽方舱的设计与应用提供一定的参考借鉴。 相似文献
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为降低钢包结构对电磁出钢系统中电源功率损耗的影响,提出了在线圈下侧与四周布置磁屏蔽材料的方法。采用数值模拟的方法分析了磁屏蔽对感应线圈周围磁感应强度和线圈最佳加热位置的影响,并通过实验进行了验证。确定了适用于电磁出钢技术的最佳的磁屏蔽尺寸和结构。结果表明,采用磁屏蔽的方法能够有效降低线圈的功率损耗,并提高线圈的最佳加热区域。当使用Cu作为磁屏蔽材料时,其最佳尺寸为高度200 mm、长度和宽度290 mm及厚度1 mm,并且网状结构在不影响水口座砖寿命的同时能够达到与传统结构基本相同的磁屏蔽效果。此时线圈的最佳加热位置会上移20.2 mm,这有利于电磁出钢系统中感应线圈的安装及其使用寿命的提高。 相似文献
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目的制备兼具良好电磁屏蔽效能和软磁性能的新型屏蔽材料。方法采用化学镀的方法在碳纤维表面制备FeNi合金涂层和Ni涂层。运用SEM、EDS、XRD分析涂层碳纤维的形貌、成分和镀层结构。通过VSM研究其软磁性能。采用万用表测量其电阻并计算电导率。利用网络矢量分析仪测量其电磁参数并计算其电磁屏蔽效能,进而对FeNi合金涂层碳纤维和Ni涂层碳纤维的上述性能进行对比。结果金属镀层均匀且晶粒细小。FeNi合金涂层碳纤维的矫顽力为29.25 Oe,饱和磁化强度为25.61 emu/g。在7.92~18 GHz频率范围内,FeNi合金涂层碳纤维的电磁屏蔽效能均在30 dB以上,峰值为40.79 dB。结论金属涂层能使碳纤维具有软磁性能,并能有效地调整其电磁参数,进而显著提高其电磁屏蔽效能。与Ni涂层碳纤维相比,FeNi合金涂层碳纤维的上述性能更加优异。该研究为兼具良好电磁屏蔽效能和软磁性能的新型屏蔽材料的制备提供了新方案。 相似文献
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抗干扰在数控系统中的设计 总被引:2,自引:0,他引:2
本文介绍了抗干扰在数控系统中的设计,从屏蔽(包括电场屏蔽、磁场屏蔽和电磁场屏蔽)设计谈起,对感性负载加吸收电路来抑制瞬态噪声做了详细说明,可避免干扰造成的数控系统的“软”故障。希望通过本文对从事数控系统的同行有一定的帮助。 相似文献
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电焊机电磁兼容技术中的几个名词术语 总被引:1,自引:0,他引:1
结出了电磁骚扰和电磁干扰的定义和区别.详细介绍了电焊机产品工作时产生的电磁骚扰包括:谐波电流发射、传导骚扰发射和辐射骚扰发射三方面的内容.分析了分贝在电焊机电磁兼容测试和电磁兼容设计方面作用. 相似文献
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电磁技术在铸造中的研究与应用 总被引:8,自引:10,他引:8
介绍了利用电磁场与金属相互作用产生的焦耳热效应和洛仑兹力效应,以及用于铸造的几种电磁加工技术,包括感应加热技术、电磁搅拌技术,电磁雾化技术,电磁约束成型技术,薄壁件移动磁场铸造技术,熔体输送技术等,这些技术在21世纪的绿色集约铸造中,将占有重要地位。 相似文献
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Zhu Luo Xian-Hua Chen Kai Song Chun-Quan Liu Yan Dai Di Zhao Fu-Sheng Pan 《金属学报(英文版)》2019,32(7):817-824
The microstructure,electrical conductivity and electromagnetic interference shielding effectiveness of Mg-X(X=Al,Sn,Y and Gd)alloys in as-cast and solution states were systematically investigated in this study.The electrical conductivity and electromagnetic shielding capacity of binary magnesium alloys decrease linearly with alloying element content.The electromagnetic shielding effectiveness of the binary magnesium alloys with the same alloying element content is as follows:Mg-GdMg-SnMg-YMg-Al.The main reason for the differences in electromagnetic interference shielding of the binary magnesium alloys is the change in conductivity,which is mainly affected by volumetric difference of solute atoms and magnesium atoms,solute atomic valence and configuration of extranuclear electron. 相似文献
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Jiahao Wang Lin Xu Ruizhi Wu Jing Feng Jinghuai Zhang Legan Hou Milin Zhang 《金属学报(英文版)》2020,33(4):490-499
High electromagnetic shielding performance was achieved in the Mg-9Li-3Al-1Zn alloy processed by accumulative roll bonding(ARB).The microstructure,electromagnetic interference shielding effectiveness(SE) in the frequency of 30-1500 MHz and mechanical properties of the alloy were investigated.A model based on the shielding of the electromagnetic plane wave was used to theoretically discuss the EMI shielding mechanisms of ARB-processed alloy.Results indicate that the SE of the material increases gradually with the increase in the ARB pass.The enhanced SE can be attributed to the obvious microstructure orientation caused by ARB,and the alternative arrangement of alpha(Mg) phase and beta(Li)phase.In addition,with the increase in ARB pass,the number of interfaces between layers increases and the grain orientation of each layer tends to alignment along c-axis,which is beneficial to the reflection loss and multiple reflection loss of the incident electromagnetic wave. 相似文献
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The effects of Ce addition on microstructure and electromagnetic interference(EMI) shielding response of Mg–6Zn–0.5Zr(ZK60) alloy have been investigated.Ce addition resulted in grain refinement and higher density of Mg–Zn–Ce and Mg Zn2 intermetallic particles in the alloy.In particular,this was substantially remarkable as the addition of Ce was up to 1.0 wt%.It is interesting to note that as-extruded ZK60 alloy with 1.0 wt% Ce addition exhibited an EMI shielding effectiveness(SE) exceeding 70 d B at the frequency range of 30–1,500 MHz,which was significantly higher than that of ZK60 alloy without Ce addition and reached the requirement of high protection.The superior SE was probably related to the increased reflection and multiple reflection of electromagnetic radiation induced by Ce addition.Direct artificial aging at 150 °C for 25 or 50 h led to a further increase of 7–10 d B in the SE of the alloy with 1.0 wt% Ce addition.The advantages of excellent shielding capacity and favorable mechanical strength make the Mg–Zn–Zr–Ce alloy an attractive shielding candidate material for a variety of technological applications. 相似文献