类金刚石薄膜在模拟体液中的电化学阻抗

利用双放电腔微波等离子体源全方位离子注入设备,分别采用等离子体增强化学气相沉积技术、等离子体源离子注入和等离子体增强化学气相沉积复合技术两种工艺对医用3161,不锈钢进行类会刚石薄膜表面改性。利用电化学阻抗谱法考察了两种工艺制备的类金刚石薄膜在模拟体液中的抗腐蚀性能。结果表明：与采用等离子体增强化学气相沉积技术制备的类金刚石薄膜相比,在72h的浸泡时间内,采用等离子体源离子注入和等离子体增强化学气相沉积复合技术制备的类金刚石薄膜防腐蚀性能明显增高,腐蚀阻抗较高,碳注入层可有效抑制溶液渗入薄膜和基体之间的界面,起到了腐蚀防护层的作用。动电位极化测试表明：采用复合技术制备的类金刚石薄膜在模拟体液中的腐蚀倾向性更低,钝态稳定性更好。     

导电聚苯胺膜的合成及其防腐性能

为了增强不锈钢(SS)双极板的耐腐蚀性能,采用循环伏安法(CV)在316L不锈钢(SS)表面电合成聚苯胺(PANI)薄膜。以0.2 M H_2SO_4+x NaCl水溶液为腐蚀介质,通过测量开路电位(OCP)、Tafel极化曲线和电化学阻抗谱(EIS),研究Cl-浓度对PANI/316L SS复合体系腐蚀行为的影响。结果显示:随着CV循环次数的增加PANI薄膜逐渐变厚;Cl~-浓度对PANI/316L SS耐腐蚀性能影响显著,随Cl~-浓度的增大,PANI/316L SS体系的耐蚀性降低。     

PECVD类金刚石涂层的结构及其摩擦腐蚀行为

采用等离子体增强化学气相沉积技术(PECVD)在316L不锈钢上制备类金刚石(DLC)涂层,系统地研究了所制备类金刚石涂层的表面形貌与结构、不同载荷下的摩擦磨损行为以及NaCl溶液(3.5 wt%)中不同腐蚀时间下的腐蚀行为。研究结果表明：制备的DLC涂层是由sp³键和sp²键杂化形成的非晶碳结构,其中sp²-C含量大于sp³-C,具有典型的类金刚石碳特征;DLC涂层结构致密,表面平滑,粗糙度仅为Ra=12.1 nm,能够与316L不锈钢基体结合紧密;DLC涂层的接触角为59.44°,说明涂层表现出一定的润湿性;摩擦磨损测试结果表明DLC涂层具有良好的润滑效果,摩擦系数能低至0.07～0.16,磨损率低至(3.85～6.71)×10^-7 mm³/(N·m);电化学测试得到DLC涂层自腐蚀电流密度为6.72×10^-6 A·cm^-2,阻抗模值高达7.05×10⁴Ω·cm^-2...     

不锈钢表面金刚石薄膜的制备与力学性能研究

在不锈钢表面沉积金刚石薄膜可以提高其耐腐蚀性、生物相容性、硬度、耐磨性,延长使用寿命,在食品和医疗器械等制品中有着广阔的应用前景。然而,在不锈钢表面直接沉积金刚石薄膜存在铁(或镍)催石墨化、应力大和易脱落的问题。我们针对这些问题开展了系统深入的研究,发展了多种在不锈钢表面沉积金刚石薄膜的新方法。如通过喷砂处理奥氏体不锈钢使其表层组织转变为热膨胀系数更小的马氏体,有效降低了金刚石薄膜的应力,提高了附着力;发展了高功率形核和低功率生长的二步降功率工艺,缓解了薄膜在高功率降温至低功率过程中的热应力;以Cr/CrSiN、Al/AlSiN等三元纳米晶/非晶复合薄膜为过渡层,通过调控界面结构和成分,在不锈钢表面制备出高结合力的致密金刚石薄膜。相关工作对于实现金刚石薄膜在不锈钢表面的应用具有较重要的意义。     

聚苯胺修饰纳米ZnO薄膜及其光致阴极保护性能

从金属材料腐蚀特性及腐蚀保护要求出发,首先利用阳极氧化法制得ZnO薄膜,再通过恒电位法将ZnO薄膜用聚苯胺修饰得到ZnO/PANI复合薄膜。采用扫描电镜分析（SEM）、X射线衍射分析（XRD）、光电流、开路电位（OCP）及电化学阻抗等方法对制得的ZnO薄膜和ZnO/PANI复合薄膜进行物性分析和光电性能评价。研究表明：成功制得ZnO/PANI复合薄膜,且表现出优良的腐蚀保护性能。OCP实验表明,ZnO/PANI复合薄膜腐蚀保护性能与纳米ZnO薄膜相比提升了2～3倍。其中,光照后ZnO薄膜的光电流增加7μA,OCP下降5mV,复合薄膜的光电流增加22μA,OCP下降13mV。最后,失重实验对两种薄膜的光致阴极保护性能的分析数据显示,ZnO薄膜和ZnO/PANI复合薄膜都能对316L不锈钢和Q235碳钢起到光致阴极保护效果,但复合薄膜对316L不锈钢的保护效果尤为明显,其受腐蚀速率与在ZnO薄膜保护状态下相比降低了1倍以上。     

浅谈304奥氏体不锈钢离子渗氮

采用直流脉冲等离子体源对304不锈钢试样表面进行离子渗氮改性,通过XRD、SEM及显微硬度计对渗氮前后的不锈钢试样表面进行成分、形貌及硬度分析,应用电化学阻抗谱分析渗氮前后试样表面的耐蚀性能。结果表明:渗氮后,不锈钢试样表面形成了γ_N相改性层,γ_N相改性层的平均硬度值为HV_(0.1N)690.1 MPa,比渗氮前的硬度提高了5倍多。与渗氮前相比,渗氮后的容抗弧直径变大,中频区相位角平台显著变宽,说明氮离子注入层使电极反应速率变慢,腐蚀速度减小,耐蚀性增强。     

聚多巴胺-聚偏氟乙烯复合膜在304不锈钢上的制备及防腐性能

采用自组装的方法用多巴胺盐酸盐溶液在经过抛光处理的304不锈钢表面形成一层聚多巴胺(PDA)薄膜,然后采用刮涂法用聚偏氟乙烯(PVDF)溶液在经过聚多巴胺改性后的不锈钢表面形成涂层。通过纳米压痕法研究了PDA–PVDF复合涂层与不锈钢基底之间的相互作用,测量了复合涂层的水接触角。借助动电位极化曲线测量和电化学阻抗谱研究了复合涂层的抗腐蚀性能。结果表明,PDA薄膜改性后的304不锈钢样品表面与PVDF涂层的粘附性大大增强,复合涂层修饰过的304不锈钢表面疏水性增强,耐腐蚀性得到了提升。     

不锈钢双极板耐腐蚀涂层制备及性能

采用室温恒压电化学氮化技术在316L不锈钢表面成功制备了氮化涂层.通过X射线光电子能谱(XPS)、电化学阻抗(EIS)、动电位极化和接触角测量等方法对涂层的组成、疏水性和耐腐蚀性进行了分析.结果表明:涂层表面主要由铬的氧化物和混合氮化物(CrN+Cr2N)组成.氮化不锈钢接触角由改性前的76.2°提高到106.7°,腐蚀电位较裸钢提高了530 mV,腐蚀电流密度下降了3个数量级,说明氮化涂层能够有效保护不锈钢基底免受腐蚀.此外,在模拟PEMFC阴极环境中进行了10 h的恒电位极化测试,腐蚀电流密度小于1μA cm-2,验证了涂层长期的稳定性.     

海洋油气开发工程316L不锈钢的腐蚀及防护

针对我国南海海洋油气平台上316L部分裸露管线腐蚀穿孔问题,进行了现场调研,调研发现管线腐蚀穿孔主要为点蚀及缝隙腐蚀。对316L不锈钢在海洋大气环境中的点蚀及缝隙腐蚀原因进行了讨论,发现海洋环境温度、氯化物应力腐蚀开裂、点腐蚀电位、表面污染及尘粒附着、工作环境、机械损伤等都是造成海洋环境中316L不锈钢局部腐蚀的重要影响因素。结合标准及试验结果,建议在南海地区裸露的不锈钢进行材质升级或者进行防腐涂装、使用防锈油脂进行防护。     

PIII氮离子注入增强沉积实验分析

等离子体浸没式离子注入(Plasma Immersion Ion Implantation—PIII)是一种新型的材料表面改性技术。它克服了传统离子注入的溅射效应,改善了注入的均匀性,消除了视线注入的限制,可处理形状复杂的工件,装置简单,并可批量生产。PIII技术存在的问题是注入能量低,注入层较浅。为克服这一缺点,本文采用将PIII技术与离子束增强沉积(IBED)相结合的复合处理方法,即等离子体浸没式离子束增强沉积(PIII-IBED)。     

底喷式等离子体发生器射流的输出特性

通过自行设计的可以综合评定等离子体射流速度、温度、压力分布等特性的实验装置,研究了底喷式等离子体射流特性。采用压电测量装置、光电测量装置和数字高速摄影研究了射流在一定距离上的压力分布特性、射流速度及射流形貌特征。结果表明,该发生器所产生等离子体射流随着距射流中心位置距离的增大迅速衰减,等离子体射流速度约500m/s,射流运动过程可分为两个阶段:第一阶段是电爆炸丝产生高温、高压等离子体射流;第二阶段是消融管消融所产生的射流。     

微波等离子体技术在纳米粉体中的应用

介绍了微波等离子体技术制备纳米粉体的原理和特点,综述了微波等离子体在纳米粉体中的应用情况。     

等离子体技术在废水处理中的应用

低温等离子体的特点在于通过放电产生的电子温度远远高于系统中其他重粒子的温度。根据这一特点．阐述了低温等离子体技术处理废水的基本原理,研究了低温等离子体对废水的处理技术,分析了低温等离子体与废水的作用过程及其机理,介绍了低温等离子体技术的国内外研究现状,最后探讨了该技术在废水处理中的应用前景及其存在的问题。     

热等离子体雾态气化制备薄膜技术

热等离子体雾态气化制备薄膜技术(mist plasma evaporation, MPE)以液态源物质溶液为先体,采用超声雾化将先体溶液雾化为细小液滴,用载气将雾化液滴输运到射频感应热等离子体中,利用热等离子体的超高温,将液滴中的源物质彻底气化和分解为其组分粒子,通过气相输运,最终在基片上沉积薄膜.MPE制备薄膜技术采用单一先体溶液,源物质来源广泛,沉积速率快,不需后续热处理.本文介绍了MPE制备薄膜技术原理及工艺,综述了近年来在制备薄膜方面的研究进展.     

Surface analysis of cotton fabrics fluorinated in radio‐frequency plasma

Cotton fabrics were treated by radio‐frequency plasma with tetrafluoromethane (CF₄) and hexafluoropropene (C₃F₆) gases under different exposure times, pressures, and power levels. The hydrophobicity and water repellency were analyzed with measurements of the cosine of the contact angle (cos θ) and wet‐out time. The hydrophobicity was enhanced with treatments of both gases. X‐ray photoelectron spectroscopy (XPS) revealed increases in the surface fluorine content of 1–2% for CF₄ plasma and of 2.3–7.8% for C₃F₆ plasma. The relative chemical composition of the C_1s spectra after CF₄ and C₃F₆ plasma treatments showed increases in the relative amounts of ? C? O? C? and fluorocarbon groups (? CF, ? CF₂, and ? CF₃), whereas peak areas for ? COH and ? COOH decreased. The hydrophobicity was enhanced by the increase in the fluorine content and fluorocarbon groups. C₃F₆ plasma treatment resulted in higher hydrophobicity than CF₄ plasma treatment according to not only cos θ and wet‐out measurements but also XPS analysis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2038–2047, 2003     

非常规等离子喷涂技术及其特点分析

本文简要介绍了反应等离子喷涂、微束等离子喷涂、层流等离子喷涂和电磁脉冲辅助-等离子喷涂等几种非常规等离子喷涂技术的原理、特点和研究现状.通过这几种非常规等离子喷涂技术特点分析,以期从中获取对未来等离子喷涂工艺发展的一些启示.     

Processing map to control the erosion of Y2O3 in fluorine based etching plasmas

Due to the increasing number of applications for ceramic components in reactive etching processes, the interest in the specific erosion behavior of highly etch-resistant materials like yttrium oxide (Y₂O₃) has increased in the past years. Despite the large number of investigations already existing in this field, a more general understanding of the erosion mechanisms still lacks due to the limited comparability of these investigations. The huge difference in the kind of etching setups, processing parameters (bias voltage and plasma gas composition), and sample microstructures prevented consistent conclusions so far. To achieve a more general understanding, this study investigates the erosion behavior Y₂O₃ under a broad spectrum of plasma etching parameters. Therefore, the bias voltage is increased from 50 to 300 V and the plasma gas composition is gradually changed from Ar-rich to CF₄-rich compositions. This systematic approach allows to directly correlate the morphology changes caused by plasma erosion with the related plasma etching parameters and enables to better understand their influence on the depth of physical and chemical interactions, surface damage, and etching rate. We discovered three distinct erosion regimes, which exhibit specific erosion characteristics. Using these observations, a schematic processing map for Y₂O₃ was developed, which could help to estimate the severity of the erosion attack dependent on the processing parameters.     

Plasma‐induced,solid‐state polymerization of N‐isopropylacrylamide

The radio‐frequency plasma‐initiated polymerization of N‐isopropylacrylamide (NIPAM) in the solid state was performed. The isolated linear polymer was characterized by ¹³C‐NMR, ¹H‐NMR, and Fourier transform infrared spectroscopy, and the effects of selected operational plasma parameters (discharge power and time) on the conversion rates were studied. Reversible transitions at the volume‐phase‐transition temperatures of the swelled poly(N‐isopropylacrylamide) hydrogels were investigated by differential scanning calorimetry. The surface morphologies before and after plasma treatment were followed by scanning electron microscopy. With the obtained X‐ray diffraction results, we propose a solid‐state plasma polymerization mechanism for the NIPAM. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Recent Advances in Prion Inactivation by Plasma Sterilizer

Prions, which cause transmissible spongiform encephalopathies (TSEs), are a notorious group of infectious agents with possibly the highest resistance to complete inactivation. Although various gas plasma instruments have been developed, studies on prion inactivation using gas plasma instruments are limited. Among them, the hydrogen peroxide gas plasma instrument, STERRAD^® (Advanced Sterilization Products; ASP, Johnson & Johnson, Irvine, CA, USA), is recommended for prion inactivation of heat-sensitive medical devices. However, STERRAD^® is not a plasma sterilizer but a hydrogen peroxide gas sterilizer. In STERRAD^®, plasma generated by radio frequency (RF) discharge removes excess hydrogen peroxide gas and does not contribute to sterilization. This is also supported by evidence that the instrument was not affected by the presence or absence of RF gas plasma. However, recent studies have shown that other gas plasma instruments derived from air, nitrogen, oxygen, Ar, and a mixture of gases using corona, dielectric barrier, microwave, and pulse discharges can inactivate scrapie prions. As inactivation studies on prions other than scrapie are limited, further accumulation of evidence on the effectiveness of gas plasma using human-derived prion samples is warranted for practical purposes.