金属双极板表面改性碳基涂层研究进展

首先对比了贵金属涂层、氮化物涂层、碳基涂层的性能优劣,重点阐述了碳基涂层改性技术的最新研究进展。然后,以碳基涂层的设计及制备2个维度为研究切入点进行阐述。在膜系设计方面,着重分析了膜系设计和元素掺杂对碳基涂层的性能影响;在制备方面,分析了偏压、沉积时间和气体流量等对碳基涂层的化学组分、微观结构的调控作用。最后,总结了当前碳基涂层改性双极板存在的问题,主要为涂层运行寿命不足,无法达到服役标准;测试条件不统一,且模拟环境与电堆实际工况差距较大;涂层长时间服役后的失效机制不明确。同时,对金属双极板改性碳基涂层的进一步发展方向做出了展望。     

质子交换膜燃料电池不锈钢双极板的腐蚀行为及其表面防护的研究进展

质子交换膜燃料电池(PEMFCs)作为一种环境友好型电池装置,在倡导人与自然和谐相处的现代社会日渐受到重视.双极板是PEMFCs的重要组成之一,其性能的好坏与PEMFCs的发展密切相关.不锈钢双极板虽具有优异的导电性和强度,但在PEMFCs的严苛工作环境下,仍面临着腐蚀与钝化等问题.近年来,国内外的研究者为解决不锈钢双极板的表面防护问题展开了广泛的探索,深入研究发现,解决这一问题的有效途径是在其表面制备高导电性、高耐蚀性的防护涂层.简述了PEMFCs的工作原理以及对双极板的性能要求,从不锈钢双极板的运行环境和工作要求出发,提出其自身存在的问题和所面临的改性难题.另外,对近年来不锈钢双极板的表面防护涂层进行了分类,分别阐述了碳基涂层、金属及其化合物涂层和疏水涂层在不锈钢双极板防护上的研究进展,分析对比了不同方法制备涂层的优缺点,在此基础上,明确了不锈钢双极板表面防护的发展方向和未来表面改性技术的研究热点.     

质子交换膜燃料电池金属双极板表面改性研究进展

双极板是质子交换膜燃料电池（Proton exchange membrane fuel cell,PEMFC）的关键部件,对燃料电池的寿命、成本及性能具有重要影响。相比于石墨双极板和碳基复合材料双极板,金属双极板体积小、强度高、导电性能优异,已成为PEMFC双极板的主流材料。然而金属双极板易在PEFMC两极环境中产生腐蚀,且极板表面生成的氧化膜会降低其导电性,严重阻碍了金属双极板的进一步应用。从金属双极板基材选材、涂层结构设计及其性能等方面综述了金属双极板表面改性研究进展,特别探讨了金属双极板金属基涂层（贵金属、金属碳/氮化物、合金等）和碳基涂层（石墨、导电聚合物、无定型碳等）的最新研究成果,从涂层的膜基结合强度、耐蚀性、导电性和疏水性等方面探讨了现有涂层的优劣,涂层结构复合和纳米化有助于提升涂层的致密性,同时可进一步提升涂层导电性和耐蚀性。如何降低金属双极板材料和表面改性成本,提高极板耐蚀性、导电性和可靠性成为双极板研究的趋势,其对PEFMC性能提升和产业化推进具有重大意义。     

纳米复合薄膜水润滑摩擦学性能的研究进展

评述了类金刚石基(DLC、a-C)、非晶氮化碳基(a-CNx)、过渡金属氮化物基(TiN、CrN)及其改性纳米复合薄膜的水润滑摩擦学性能,分析了微观结构、梯度结构、元素掺杂、对磨材料及摩擦参数对其水润滑摩擦磨损性能的影响,并揭示了水润滑中纳米复合薄膜存在的摩擦磨损机制,指出了三种纳米复合薄膜体系在水润滑中均可表现出优异的减摩抗磨特性,但与薄膜成分、层状结构、力学性能及对磨材料物理化学性能密切相关。一般而言,相比于过渡金属氮化物基薄膜,类金刚石基及非晶氮化碳基薄膜由于在水润滑中形成转移层和水合润滑层而呈现出更低的摩擦系数和磨损率。当选用的对磨材料易于发生摩擦水合反应时,形成的水合层起到的保护作用使得纳米复合薄膜均表现出了更低的磨损率。在保证薄膜未发生剥落而失效时,适当地加载载荷和滑移速度也是获得最优水润滑摩擦学性能的关键因素。为薄膜应用在水润滑器械作业提供了一定的参考,并展望了纳米复合薄膜水润滑摩擦学未来的研究方向。     

超音速火焰喷涂铁基非晶涂层的微观组织及性能

为增强海洋工程装备中关键部件的耐磨与抗腐蚀性能,采用超音速火焰喷涂(HVOF)技术在不锈钢基体表面喷涂Fe基非晶涂层。利用SEM、XRD和DSC等,对该涂层的微观组织、相结构及性能进行了分析。研究了喷涂中煤油流量、氧气流量、喷距对非晶涂层微观组织和性能的影响。结果表明,超音速火焰喷涂制备的铁基非晶涂层组织结构均匀致密,呈完全非晶态结构。喷涂工艺参数对涂层的显微硬度具有重要影响,在优化工艺参数下获得的显微硬度为912.1 HV0.3。不锈钢喷涂非晶涂层后耐磨性提高。     

TiN涂层电化学腐蚀行为研究Ⅰ.TiN涂层的保护性能与失效机制

利用电化学方法以及扫描电镜 (SEM )、扫描隧道显微镜 (STM )等技术 ,研究了离子镀TiN薄膜涂层在 0 5mol/LNaCl和 1mol/LH2 SO4溶液中的保护性能和失效机制 .结果表明 :TiN涂层可以提高材料在中性和酸性溶液中的耐蚀性能 ,TiN涂层的保护机制为物理屏障作用 ;镀层的微观结构缺陷是涂层失效的主要原因 ,涂层下金属的腐蚀行为与孔蚀类似     

TiN涂层电化学腐蚀行为研究I．TiN涂层的保护性能与失效机制

利用电化学方法以及扫描电镜(SEM)、扫描隧道显微镜(STM)等技术，研究了离子镀TiN薄膜涂层在0．5mol NaCl和lmol/L H2SO4溶液中的保护性能和失效机制、结果表明：TiN涂层可以提高材料在中性和酸性溶液中的耐蚀性能，TiN涂层的保护机制为物理屏障作用；镀层的微观结构缺陷是涂层失效的主要原因，涂层下金属的腐蚀行为与孔蚀类似。     

电机轴承防护措施及Al2O3陶瓷绝缘涂层研究现状

讨论了避免电机轴承电蚀失效的主要防护措施,包括安装接地碳刷疏导轴电流、使用绝缘轴承截断轴电流这两类方式,并对其优缺点分别进行了阐述.针对绝缘轴承,着重分析了Al2O3陶瓷涂层的热喷涂工艺(粉末粒径、喷涂参数等)、涂层结构(表面形貌与微观组织)以及涂层性能(力学性能、摩擦性能、绝缘性能)三者间的关系,介绍了通过掺杂其他金属阳离子氧化物或纳米结构粉末对涂层性能进行改性的方法.在此基础上,对绝缘轴承Al2O3陶瓷涂层制备技术存在的难点进行了分析,总结了存在的主要问题.最后对绝缘轴承Al2O3陶瓷涂层制备技术的发展趋势进行了展望.     

海洋环境下物理气相沉积氮/碳基抗磨蚀涂层的研究进展

主要综述了海洋环境抗磨蚀防护涂层及技术的发展现状,对比了喷涂、高能束表面改性、物理气相沉积(Physical vapor deposition,PVD)三种常用技术的优劣势,并归纳了不同涂层在海水磨蚀条件下的磨损率和腐蚀电流密度,发现PVD制备的氮/碳基涂层呈现出更优的耐摩擦防腐蚀性能.进一步对海洋环境氮基与碳基抗磨蚀防护涂层的研究成果进行了重点阐述,探讨了组分、过渡层以及多层结构设计等对涂层微结构、力学及磨蚀性能的影响,剖析了涂层在海水磨蚀环境中的失效分析方法和损伤机理.最后,对海洋抗磨蚀防护涂层的未来发展方向进行了思考与展望.     

质子交换膜燃料电池双极板防护涂层研究进展

质子交换膜燃料电池(PEMFC)作为第4代发电技术,具有结构紧凑、体积小、能量密度高、效率高、启动快、低温运行以及零排放的绝对优势,被认为是现阶段理想的清洁能源之一,是未来新能源汽车理想的供能部件,受到各国学者的广泛关注。双极板作为PEMFC重要的组成部件之一,不仅能够将单电池串联、并联或是混合联结形成电池堆,起到支撑作用,还能够隔绝阴极、阳极的反应气体,排出电池堆反应产生的热量和水,对PEMFC电池堆的性能至关重要。合适的双极板材料要具有优异的导电性和耐腐蚀性,已成为PEMFC研究领域的一个热点。简述了PEMFC的工作原理以及近年来石墨双极板、金属双极板以及复合双极板的研究情况,指出了PEMFC在工作条件下对金属双极板的性能要求及改性难题。着重对不锈钢双极板的表面涂层改性进行了研究,列举了碳基涂层、金属及其化合物涂层、导电高分子聚合物涂层、疏水涂层等一系列涂层的研究进展和性能,分析对比了它们在PEMFC双极板表面改性中的优缺点。分析结果表明,过渡金属碳、氮化物以及碳/陶瓷复合涂层具有良好的导电性和耐蚀性且成本较低,是当前以及未来的研究热点,同时如何增强涂层与基体的结合力,也是今后双极...     

氢燃料电池中钛双极板研究进展

钛及钛合金密度低、比强度高且在酸性环境中耐蚀性优异,在氢燃料电池双极板中具有较高的应用价值。回顾了近年来氢燃料电池用钛双极板的研究进展,详述了钛双极板表面改性技术的研究成果,包括掺杂合金元素、钛表面涂覆金属基涂层(贵金属、金属碳/氮化物等)和碳基涂层(石墨、无定型碳等)。涂层结构组织的复合化和纳米化,有利于提升钛双极板的耐蚀性、导电性和疏水性,其对于提升氢燃料电池的性能及保证其运行的稳定性和耐久性具有重要作用。     

Performance Degradation of TiN-and TiC-deposited AISI316 bipolar plates for proton exchange membrane fuel cells

TiN and TiC were deposited on AISI316 bipolar plates for proton exchange membrane fuel cells (PEMFCs) and their effects on the corrosion resistance and overall cell performance were investigated. TiN with a Ti interlayer and TiC with a Ti interlayer were deposited on AISI316 bipolar plates by hollow cathode discharge (HCD) ion plating. The electrochemical behavior of the metallic bipolar plates was examined using a potentiodynamic method, an electrochemical impedance spectroscopy (EIS), and a single cell test. These results revealed that the TiN and TiC coatings considerably improved the corrosion resistance of AISI316. However, the TiN-deposited AISI316 bipolar plates showed a better cell performance than the TiC-deposited AISI316 bipolar plates. The differences in the cell performance stemmed from the differences in the ohmic resistance and charge transfer resistance.     

质子交换膜燃料电池极板及其表面改性研究进展

在质子交换膜燃料电池（Proton exchange membrane fuel cells,PEMFCs）的部件中,双极板是重要组成部分。双极板约占燃料电池成本、质量、体积的40 %、80 %、50 %。传统的PEMFC因为石墨双极板的材料、工艺等问题,造成其体积和质量较大,这增加了汽车的重量,缩小了汽车底盘地可用空间,影响了质子交换膜燃料电池汽车的性能。因此开发体积小、成本低、制备工艺简单的双极板对推进质子交换膜燃料电池的商业化应用具有重要意义。金属双极板因其成本低、力学性能好、导电性、导热性、体积相对易控等特点,在PEMFC领域备受关注。但金属双极板在PEMFC环境中易生成钝化膜,导致其接触电阻增加。因此,如何在提高金属双极板耐蚀性的同时,保持良好的导电性,是当前对PEMFC研究的重点。本文综述了石墨、复合材料和金属双极板制备工艺及表面改性方法。讨论了双极板及其表面碳化物涂层、金属涂层和氮化物涂层的优缺点,并比较了这些涂层在PEMFC环境下的耐腐蚀性和界面接触电阻性能。     

Adhesion and dynamic impact wear of nanocomposite TiC-based coatings prepared by DCMS and HiPIMS

Nanocomposite nc-TiC/a-C:H coatings exhibit a unique combination of mechanical properties such as high hardness, and low friction and wear. These physical and mechanical properties make those coatings attractive for application in industry. However, the properties of the whole coating/substrate system such as adhesion of the coating to substrate and its response on repeated impact loading known such as dynamic impact wear are also important for industrial applications. Thus, this paper is focused on the adhesion and the dynamic impact wear of nc-TiC/a-C:H coatings prepared by the hybrid PVD-PECVD process. Two series of nc-TiC/a-C:H coatings with a different amount of carbon were deposited onto commonly used industrial cemented tungsten carbide substrates using DC magnetron sputtering (DCMS) and the high power impulse magnetron sputtering (HiPIMS) of a titanium target in argon and acetylene mixture atmosphere. Both series of coatings were analysed using a scratch test and dynamic impact tester with an impact load of 600 N. The HiPIMS prepared coatings exhibited lower thickness and lower thicknesses of the Ti adhesive interlayers between the substrates and coatings than the DCMS prepared coatings. Thus, the adhesion and the impact wear of both series were discussed separately. These properties were discussed with respect to the coating microstructure, phase composition and mechanical properties such as the hardness H, the effective elastic modulus E, and the H/E and H³/E² ratios. The scratch adhesion of coatings depended on the H³/E² ratio and coating microstructure, hardness and surface roughness. The impact wear of the nc-TiC/a-C:H coatings depended on the H/E ratio and coating microstructure.     

高能微弧合金化沉积氮化物陶瓷覆盖层及其耐蚀性能分析

采用高能微弧合金化技术沉积TiCN冶金结合涂层,用于金属双极板的表面防护。沉积过程中的参数,如输出电压、功率、频率、气流量等对沉积层耐蚀性的影响较大。随着功率增加,TiCN涂层在304不锈钢基体上的沉积圈半径由小变大,且对应酸性溶液中腐蚀电流密度随功率的增大而减小;随频率的增加,单点脉冲放电能量是呈减小的趋势,且腐蚀电流密度随频率的增大而增大,这与沉积过程中的输出能量相关。     

Controlling friction and wear of nc-WC/a-C(Al) nanocomposite coating by lubricant/additive synergies

Owing to increasing demands for reductions in emissions and improvements in fuel economy in the automotive industry, there is an urgent need to improve tribological performances of components. In the current paper, an nc-WC/a-C(Al) carbon-based nanocomposite coating was fabricated successfully via the magnetron sputtering process. The microstructure and mechanical properties of the as-fabricated nanocomposite coating were investigated. In particular, its friction and wear behaviors under poly-alpha-olefin oil lubricant added with anti-wear (AW), extreme-pressure (EP), or molybdenum dialkyldithiocarbamate (MoDTC) additive were systemically evaluated. Results show that the nc-WC/a-C(Al) nanocomposite coating has a typical nanocrystallite/amorphous microstructure and good mechanical properties. The significant improvement in the tribological performance of the boundary-lubricated nc-WC/a-C(Al) coating is mainly attributed to the WS₂ or MoS₂ + WS₂-containing tribofilm when S-based EP or MoDTC additive was used. Superior tribological performance of nc-WC/a-C(Al) nanocomposite coating was achieved by lubricant/additive synergies, indicating its potential application as a protective coating for automotive tribo-components.     

Tribological behaviour of titanium carbide/amorphous carbon nanocomposite coatings: From macro to the micro-scale

The tribological behaviour of nanocomposite coatings made of nanocrystalline metal carbides and amorphous carbon (a-C) prepared by PVD/CVD techniques is found to be very dependant on the film deposition technique, synthesis conditions and testing parameters. Focusing in the TiC/amorphous carbon-based nanostructured system, this paper is devoted to an assessment of the factors governing the tribological performance of this family of nanocomposites using a series of TiC/a-C films prepared by magnetron sputtering technique varying the power applied to each target (titanium or graphite) as model system to establish correlations between film microstructure and chemical compositions and tribological properties measured by a pin-on-disk tribometer. The film microstructure goes from a quasi-polycrystalline TiC to a nanocomposite formed by nanocrystals of TiC embedded in an amorphous carbon matrix as observed by transmission electron microscopy (TEM). The nanocrystalline/amorphous ratio appears to be the key-parameter to control the tribological properties and its quantification has been done by electron energy-loss spectroscopy (EELS). A significant change in the tribological performance is observed for nanocomposites with amorphous carbon phase contents above 60–65%. The friction coefficient decreases from 0.3 to 0.1 and the film wear rates by a factor of 10. Examination of the wear scars on ball and film surfaces by laser micro-Raman spectroscopy has allowed to determine the presence of metallic oxides and carbonaceous compounds responsible of the observed friction behaviour. The revision of the literature results in view of the conclusions obtained enabled to explain their apparent dispersion in the tribological performance.     

雷达吸波涂层材料的研究进展

讨论了电磁波的吸波机理,及其性能测量和计算方法,叙述了电阻型损耗、介电损耗、磁损耗型三种损耗机制的涂层材料及其电磁波吸收损耗机理,对不同种类的吸波材料在雷达波隐身方面的应用进行了全面的综述,介绍了这一研究方向的最新进展,并分析了每种材料的主要特点。重点讨论了铁氧体、碳纳米管、导电高聚物等吸波材料的微观结构、化学性质、电磁特性对吸波性能的影响。对于磁损耗材料来说,良好的磁性能是其不可忽视的优点,但其密度高,稳定性较差,影响了其性能发挥。针对其存在的缺点,通过掺杂改性、共混等方式可提升涂层材料的吸波性能。在碳系材料中,多壁碳纳米管的吸波性能较好,将磁损耗吸波材料与碳纳米管进行复合、包覆是目前吸波性能提高的主要手段。导电聚合物等新型吸波材料具有质量轻、导电性好的特点,单独使用时,阻抗匹配性差,通过对其掺杂改性或与磁损耗型材料复合,可增强其阻抗匹配性,提升吸波性能。最后,指出了雷达吸波材料未来的研究发展方向。