Negative ion etching of Al−Si−Cu by employing a magnetic filter in halogen plasmas

Al etching was studied employing negative ions generated in downstream Cl₂ plasma. The Al etch rate by the alternate irradiation of positive and negative ions was two times higher than that by usual positive ions. In order to etch the Al film practically on an insulator covered electrode coupled with RF power, reduction of the negative self bias voltage (Vdc) was examined using a magnetic filter which traps electrons. The reason for the high etching reactivity is that the dominant negative ions F in SF₆ and Cl⁻ in Cl₂ plasmas are atomically very similar to the radicals. Addition of SF₆ and H₂ to a Cl₂/BCl₃ mixture reduced Vdc significantly. However, fluorine and hydrogen atoms inhibited Al etching in spite of sufficient ion energy.     

气体氮碳共渗钢板表面粗糙度和形貌的研究

研究了抛光冷轧钢板气体氮碳共渗时氨流量对共渗层表面粗糙度和形貌的影响。用扫描电镜和表面粗糙度仪对氮碳共渗层的表面形貌进行观察和测定。结果表明，随氨流量的增大，氮碳共渗层表面的粗糙度减小，表面组织细小致密。当氨流量小于1．0m^3／h时，表面粗糙度随共渗时间的延长逐步增大。钢板表面粗糙度与工件在炉中的位置和排布方式以及氨分解率有关。     

Technology of thermally sprayed anilox rolls: State of art,problems, and perspectives

This paper deals with the surfacing technology of ceramic anilox rolls. The rolls are used in the printing industry to transport the precisely determined quantity of ink in the flexographic printing machines. The technology of roll surfacing is discussed by taking the following aspects into account: preparation of the powder to spray the ceramic coating; thermal spraying of the duplex (bond coating and ceramic top coating); postspray finishing by grinding and polishing; and laser engraving. The powder used as the top coating of the aniloxes is chromium oxide. This powder might be prepared by such techniques as agglomeration, fusing, and crushing, etc. The preparation technique influences coating properties, such as microstructure (tested with SEM, OM, XRD, and XPS), open porosity, microhardness, and modulus of elasticity. Comparison of these properties enables optimum powder preparation techniques to be found. APS technique is used to coat the anilox rolls. Optimization of the plasma spraying parameters is discussed. Aniloxes are submitted to the grinding and polishing of the ceramic coating before laser engraving occurs. The final roughness of the finished coating is discussed in view of an optimum absorption of the laser light energy at engraving. Possible ways of reducing the spraying time are discussed, and future research toward improving the anilox roll quality is proposed.     

脉冲高能量密度等离子体沉积氮化钛膜的结合强度

本文用脉冲高能量密度等离子体技术，在室温条件下，成功地在ＧＣｒ１５钢表面沉积了性能良好的氮化钛薄膜。用自动划痕试验仪测量了氮化钛薄膜的结合强度。研究结果表明：表征薄膜结合强度的临界载荷有相当高的值；氮化钛薄膜的临界载荷随脉冲轰击次数、内外电极的电压变化而变化。对沉积膜结合强度的这些变化给予了理论上的解释与讨论。     

45钢的离子氮碳共渗-离子渗氧复合处理

研究了45钢离子氮碳共渗-离子渗氧复合处理工艺。试验表明，45钢经离子氮碳共渗-离子渗氧复合处理后，表层可获得化合物和氧化物的复合层，该复合处理可以明显提高45钢的耐磨性。     

碳基钨涂层在退火过程中的组织和结构变化

用真空等离子体喷涂(VPS)技术在C／C复合材料基体上制备了厚度为0．5mm的钨(W)涂层，涂层的表面通过物理气相沉积(PVD)预沉积钨、铼(Re)多层作为碳(C)的扩散势垒。涂层经过1200℃--2000℃的电子束退火，其微观结构和化学构成发生变化。经测量涂层的再结晶温度约为1400℃，再结晶的活性能为63kJ／mol。当退火温度高于1300℃时，涂层表面的多层W、Re结构将由于W、Re和C之间的相互扩散而发生改变，并在1600℃以上退火lh后由于脆性碳化钨在界面的形成而完全失效，碳化钨层的厚度将随着退火漏度的升高和退火时间的延长而迅速增加。     

TIG焊和PAW焊中活性剂对焊缝熔深的影响

针对常规TIG焊生产效率低、熔深小等问题，研究了TIG焊和PAW焊中应用活性剂对焊缝熔深的影响。结果表明，应用活性剂后，在同样的参数下，同传统TIG相比，活性剂能够大幅度提高不锈钢、铝合金和钛合金的焊缝熔深。对于PAW焊，熔深也有增加，但是增加的幅度不如TIG效果明显，但对焊缝成形有很好的改善。同时，活性剂对铝合金焊接背面能够起到保护作用。对于钛合金，活性剂除了增加焊缝的熔深外，还能够大幅度地消减焊缝产生的气孔。     

Optimization of spraying process and laser treatment of CoNiCrAlY

This article describes the investigation of a new generation of vacuum plasma sprayed CoNiCrAlY coatings on NiCr20Ti in the sprayed as well as the laser-treated condition. The aim of the study was the improvement of MCrAlY coating properties by modifying the microstructure through laser remelting with 5-kW Co₂: lasers. Parameter analysis and optimization was carried out for the vacuum plasma spraying process, as well as for the laser remelting technique. The effect of the laser treatment on microstructure, quality of the coatings, and oxidation as well as hot gas corrosion behavior are reported.     

等离子态氢还原金属氧化物初探

把分子态的氢转变为等离子态的氢可以从热力学和动力学层面上提高氢还原金属氧化物的能力.中等气压下(102～104 Pa)非平衡态氢等离子体中存在的主要活泼粒子包括H、H 、H 2和H 3,其中原子氢的浓度最大,是比较稳定且具有重要化学反应活性的粒子.根据热力学计算,这些粒子的还原能力大小为:H >H 2>H 3 >H.通过CuO在直流脉冲辉光氢等离子体中的还原实验证实了等离子态的氢能强化氢还原金属氧化物的能力.     

Characterization of YSZ solid oxide fuel cells electrolyte deposited by atmospheric plasma spraying and low pressure plasma spraying

Yttria doped zirconia has been widely used as electrolyte materials for solid oxide fuel cells (SOFC). Plasma spraying is a cost-effective process to deposit YSZ electrolyte. In this study, the 8 mol% Y₂O₃ stabilized ZrO₂ (YSZ) layer was deposited by low pressure plasma spraying (LPPS) and atmospheric plasma spraying (APS) with fused-crushed and agglomerated powders to examine the effect of spray method and particle size on the electrical conductivity and gas permeability of YSZ coating. The microstructure of YSZ coating was characterized by scanning electron microscopy and x-ray diffraction analysis. The results showed that the gas permeability was significantly influenced by powder structure. The gas permeability of YSZ coating deposited by fused-crushed powder is one order lower in magnitude than that by agglomerated powder. Moreover, the gas permeability of YSZ deposited by LPPS is lower than that of APS YSZ. The electrical conductivity of the deposits through thickness direction was measured by potentiostat/galvanostat based on three-electrode assembly approach. The electrical conductivity of YSZ coating deposited by low pressure plasma spraying with fused-crushed powder of small particle size was 0.043 S cm⁻¹ at 100 °C, which is about 20% higher than that of atmospheric plasma spraying YSZ with the same powder. This article was originally published inBuilding on 100 Years of Success, Proceedings of the 2006 International Thermal Spray Conference (Seattle, WA), May 15–18, 2006, B.R. Marple, M.M. Hyland, Y.-Ch. Lau, R.S. Lima, and J. Voyer, Ed., ASM International, Materials Park, OH, 2006.