高功率脉冲磁控溅射复合电源及其电弧特性研究

高功率脉冲磁控溅射因其高离化率得到广泛关注,是磁控溅射领域的新方向。随着对高功率脉冲磁控溅射放电和等离子特性的深入研究,制约高功率脉冲磁控溅射应用的主要不足有:沉积速率低,容易进入电弧放电影响膜层品质。本文从电源角度出发,针对高功率脉冲磁控溅射的高功率大电流特点,采用复合直流/脉冲电源提升高功率脉冲磁控溅射的沉积速率,采用电弧抑制电路避免电弧对膜层品质的危害。结果表明,复合高功率脉冲磁控溅射电源的设计有利于改善沉积速率;电弧抑制电路可快速检测,并通过电弧抑制回路快速释放残存能量,避免了电弧对高功率脉冲磁控溅射的影响。     

基于Simulink的三相桥式全控整流电路的仿真研究

整流电路是电力电子电路中出现最早的一种,它将交流电变为直流电,应用十分广‘泛,电路的形式也是多种多样,各具特色。三相桥式全控整流电路在现代电力电子技术中应用广泛并具有非常重要的作用。在对三相桥式全控整流电路作出理论分析的基础上,应Matlab的可视化仿真工具Simulink建立了三相桥式全控整流电路的仿真模型,通过改变触发角对三相桥式全控整流电路的输出电压影响进行了仿真分析。结果表明,仿真波形与常规分析方法得到的结果具有一致性,从而得到了一种直观、快捷分析整流电路的方法。     

直流电机双闭环调速系统设计

双闭环直流调速系统是工业生产过程中应用最广泛的电气传动装置之一。本文主要是根据三相全波相控整流电路的原理,选择合适的变压器、晶闸管、平波电抗器以及晶闸管保护、触发电路,组成整流电路。     

井冈山GX98放映机电源及其控制电路的工作原理

井冈山 GX98型 3 5mm固定式电影放映机在整流电源方面 ,主要采用了三相半控桥式整流电路 ,利用压控振荡器产生移相电路的控制电压 ,控制三只可控硅的导通角 ;在控制电路中采用了定时发生器 ,利用分频器对主时钟频率进行分频 ,产生三个时间信号 ,对放映操作实施相应的控制。图 1为该机电路主要结构方框图 ,以定时发生器为中心的自动控制电路、以各种控制开关为中心的手动控制电路与激励灯控制电路共同完成对放映机、电磁光闸、激励灯的控制功能。其整流电源部分的结构形式与GX4、GX5固定机及流动机相似 ,但在功能的实现方式上却有了很大的…     

一种应用于碳纳米管制备的交流脉冲电源研制

研制了一台零电压软开关中频交流脉冲放电电源,应用于碳纳米管的制备,以乙炔作为碳源,在反应容器中通入氦气,在两电极之间激发出电弧为碳纳米管生长提供环境。本文给出了交流脉冲电源的设计思路和实现方案。该电源采用三相桥式不可控整流拓扑电路、PWM整流电路、半桥逆变电路的方案。根据放电过程中电流急剧上升的特点,绕制了具有高漏感的变压器,利用变压器漏感来抑制放电过程电流上升的速率,同时实现了IGBT的零电压开通。该电源输出峰值电压5kv-12kv连续可调,频率为8k Hz,脉宽占空比16%~20%可调。通过对放电试验结果的观测,此电源各项指标运行正常,工作稳定,电磁干扰小,具有良好的应用价值。     

基于整流与逆变原理的高压直流输电技术分析

高压直流输电中的换流阀由晶闸管级串联组成的。每个晶闸管级由直流均压电路,交流均压电路,晶闸管控制单元和晶闸管组成．其中晶闸管控制单元是核心。本文首先阐明晶闸管在三相桥式全控整流与逆变过程中的运行方式;然后说明基于整流与逆变原理,晶闸管在高压直流输电技术中的应用。     

基于单片机AT89S52的晶闸管触发电路设计

该文阐述了基于单片机AT89S52构成的三相半波可控整流电路晶闸管触发电路的设计，介绍了AT89S52单片机控制的触发装置的硬件与软件设计，并且成功地改造了KGT-1型晶闸管调速装置。     

基于PCA神经网络的电路电子整流装置故障诊断方法

提出一种基于PCA-神经网络的电力电子整流装置故障诊断方法.首先对故障信号用主元分析法(PCA)提取特征向量.然后用神经网络进行训练和测试.通过三相可控整流电路晶闸管断路故障诊断实验结果表明,该方法能够简化神经网络的结构,提高网络的训练速度,并获得了很好的诊断效果.     

基于Multisim的串联12脉波整流电路仿真与谐波分析

12脉波整流电路在高压直流输电等实际工程项目中应用广泛。本文利用Multisim软件对串联12脉波整流电路进行仿真分析,模拟整流电路的工作状况。然后结合软件的傅里叶分析等功能,研究整流输出电压的谐波情况。最后,对这一仿真过程进行简要评估。     

从两例特殊故障谈对光源整流设备定期保养的重要性

笔者在基层电影院检修光源整流设备中 ,曾碰到两例特殊故障 ,虽然比较少见 ,但其原因带有很大的普遍性。例一 ,一台 GFA0 1- 150 /35型硅整流器 ,系磁放大器控制式整流设备 ,空载直流输出电压仅 4 0 V(正常值应大于或等于 90 V) ,氙灯无法点燃。检查外电路交流输入电压正常 ,机体内三相熔断器 ,交流接触器及主整流二极管均完好 ,各导线及其接头均未发现接触不良等异常现象 ;从测量三相整流电路的交流输入电压 (即主变压器次级输出电压 )发现三相交流电压不平衡 ,并发现电压偏低的那个主变压器外表有碱湿干后的迹象 ;进一步仔细检查 ,发现…     

多功能复合离子镀膜机的研制

详细介绍了一台我院新近研制的多功能复合离子镀膜机.该机配有柱弧源、电磁控大面积弧源、小多弧源,使得在不同材质的工件上原位连续镀制各种多层膜及复合化合物膜;偏压电源采用我院自行开发的叠加式直流脉冲偏压开关电源,使用该电源可有效控制基体温度,实现远离平衡态的低温沉积镀膜工艺;全部控制及工艺流程采用PLC(可编程控制器)自动控制,具有成本低、效率高、膜系质量优、工艺可重复性好等特点.用该设备开发的一些功能膜复合工艺已获得实际应用,取得了良好的使用效果.     

磁控溅射工艺参数对涤纶织物表面沉积铜膜性能的影响

在室温条件下采用射频磁控溅射法在涤纶平纹机织物表面沉积纳米Cu薄膜,借助原子力显微镜(AFM)观察镀膜前后样品表面变化。通过分别改变镀膜时间、溅射功率和气体压强,研究其对样品透光性和导电性的影响。实验结果表明,经Cu镀层处理的涤纶平纹织物对紫外光和可见光的吸收能力明显优于原样。溅射压强增加,透光性能增强,铜膜方块电阻增加,导电性能减弱;镀膜时间延长和溅射功率增加,样品透射率降低,屏蔽紫外线和可见光效果明显,在溅射时间接近15min和溅射功率增加到120W后,样品屏蔽效果不明显,铜膜方块电阻随溅射功率增加而减小,导电性能增强。     

Deposition of photocatalytic titania coatings on polymeric substrates by HiPIMS

Titania coatings have been deposited onto PET substrates by reactive magnetron sputtering in the HiPIMS (high power impulse magnetron sputtering) mode and for comparison, pulsed DC mode. In the latter case, the substrate showed evidence of melting, but the HiPIMS results were dependent on the characteristics of the power supply when operating under nominally identical conditions. A coating deposited by one of the HiPIMS supplies was found to have a mixed phase structure and to demonstrate a level of photocatalytic activity comparable to conventional coatings which had been post-deposition annealed.     

射频电源有关问题的探讨

在射频溅射镀膜中,射频电源的反射功率偏大和靶打火一直是困扰行业的问题,本文从理论上说明射频系统和网络匹配问题,并结合实际和试验,讨论如何降低反射功率和减少靶打火的问题,并提供解决问题的相关资料,以资说明.     

透明陶瓷保护膜的研究

对黄铜基材装饰件表面先采用高能级磁控溅射离子镀(专利号:85102600.1)技术镀不锈钢代替电镀钯-镍合金,再采用等离子体型阴极弧源-磁控溅射镀(专利号:ZL98236950.6)技术在不锈钢镀膜表面上镀制TiN/Au/透明陶瓷保护膜SiO2、TiO2.对其硬度、耐蚀性及耐磨性进行分析.     

Higher Tool Productivity due to New Generation of PVD Coatings

PVD coating technology has seen many new developments in the past few years. HIPIMS⁺ is an example of these developments with excellent results on tool productivity and lifespan. The technology combines the advantages of arc evaporation with those of magnetron sputtering and results in a dense and defect‐free coating with tuneable residual stress. The coatings have been tested successfully by international tool manufacturers. Additional developments can be seen in DLC coatings and the hydrogen‐free variety ta‐C. These coatings are suitable for low temperature deposition and machining of special materials.     

28CrMo钢表面磁控溅射TiN涂层的组织结构及耐腐蚀性能

为了提高28CrMo钢表面的致密性和耐腐蚀性能,采用磁控溅射技术在28CrMo钢表面制备TiN涂层,通过光学显微镜、X射线衍射仪(XRD)、电化学测试等手段分析了TiN涂层的显微结构及其在3.5%NaCl溶液中的耐腐蚀性能。结果表明:采用磁控溅射技术在28CrMo钢表面制备了厚约0.5μm的TiN涂层,涂层与基体结合良好,没有出现明显的裂纹,涂层表面N的原子分数明显高于Ti;电化学Nyquist谱得到高频区的容抗弧可能是由电荷转移电阻引起和膜层引起,中频区的容抗弧由基体金属溶解时的传质弛豫引起,低频区的感抗弧由基体表面吸附物的弛豫过程引起;3.5%NaCl溶液中腐蚀96 h后TiN涂层表面有蚀坑,吸附有白色疏松的腐蚀产物,并出现大小不一的腐蚀坑;TiN涂层能够明显改善基体的耐蚀性能,对改进高铬钢表面特性具有重要的作用。     

Field Application of Automated Power Arc Spraying System on Steel Bridge Deck

The effective corrosion protection coating and high productive coating equipment for steel bridge deck has been a challenge for bridge engineers for many years. An automated power arc spraying system was first designed and field applied to coating the deck of Wuhan Junshan Yangtze River Bridge in high efficiency. This steel bridge is a continuous orthotropic deck box girder cable-stayed bridge with 962 m in length and 38.8 m in width, whose width is the No. 1 in China. The whole orthotropic deck with over 35,000 m2surface area was arc-sprayed a protective coating of zinc on site, followed by a sealant and SMA paving material. The side face and bottom of box girders were arc-sprayed with aluminum in factory.Field application indicated that the newly designed automated power arc spraying system with fan nozzle and separate primary & secondary atomizing air had some advantages over the conventional arc spraying system, such as automated operation,big arc spray current, high spraying rate, big breadth of each coat, even and small atomized particles, high density and low porosity of sprayed coating, and high adhesive strength to the substrate.Working procedure of surface preparation and automated arc spraying on bridge deck were introduced, and the quality of sprayed coating is controlled strictly. Field tests proved that the application of this automated power arc spraying system is successful and suitable for coating the steel bridge deck.     

Abscheidung von SiOxNy Sperrschichten durch Dual Magnetron Sputtering

Silicon Oxynitride Barrier Layers Deposited by Pulsed‐DC Dual Magnetron Sputtering SiO_xN_y barrier layers have been deposited using pulsed direct current (DC) and medium frequency (MF) sputtering on large area (GEN 5) glass substrates. Several process parameters, such as discharge voltage, boost voltage, and discharge frequency were varied with the goal of increasing system productivity and reducing the arc rate during SiO_xN_y deposition. The arc rate during operation with pulsed DC dual magnetron sputtering was lower than for MF sputtering; however for the same nominal discharge power, the deposition rate using pulsed DC power supplies was slightly lower than for operation with MF. The suitability for use as a barrier layer was deduced by capping the SiO_xN_y layers with DC sputtered ZnO:Al coatings and subjecting the sample stacks to anodic and cathodic degradation and subsequent storage in a damp atmosphere.     

A comparative research on magnetron sputtering and arc evaporation deposition of Ti-Al-N coatings

Ti-Al-N coating has been proven to be an effective protective coating for machining applications. Here, the differences of cubic Ti-Al-N coatings with a similar Ti/Al atomic ratio of 1 deposited by magnetron sputtering and cathodic arc evaporation have been studied in detail. Main emphasis was laid on the characterization of thermal stability and cutting performance. Both coatings during annealing exhibit a structural transformation into stable phases c-TiN and h-AlN via an intermediate step of spiondal decomposition with the precipitation of c-AlN, however, a difference in decomposition process. Compared to sputtered coating inserts, an increase of tool life-time by 42% is obtained by evaporated coating inserts at the higher speed of 200 m/min, whereas the similar cutting life is observed at the speed of 160 m/min. It is attributed to the better stability of evaporated coating due to its later structural transformation at elevated temperature. A post-deposition vacuum annealing of both coated inserts in their corresponding temperature range of spiondal decomposition improves their cutting performance due to an increase in hardness arising from the precipitation of coherent cubic-phase nanometer-size c-AlN domains. Additionally, the sputtered coating behaves in worse oxidation resistance due to its more open structure. These behaviors can be understood considering the difference in microstructure and morphology of as deposited coatings originating from adatom mobility of deposited particles, where arc evaporation technique with higher ion to neutral ratio shows higher adatom mobility.