共查询到19条相似文献,搜索用时 125 毫秒
1.
2.
本文对3种防腐涂料进行了模拟深海压力交变环境下的防腐试验,对涂层吸水率、附着力、表面形貌、耐阴极剥离性及抗氯离子渗透性进行了测试。试验结果表明,在压力交变环境下,涂层受到压缩与膨胀的相互作用,涂层内部的孔隙增大,氯离子、水和氧气等腐蚀介质较常压下更容易渗透进入涂层或渗入到涂层与底材的连接界面,使涂层的吸水过程加快并导致涂层阴极剥离及抗氯离子渗透性能大大降低。从涂层表面形貌上看,腐蚀介质渗入和聚积导致了涂层内可溶物质析出,并随着涂层内部传输路径扩散到涂层表面,最终出现涂层开裂等现象。 相似文献
3.
4.
5.
采用电弧离子镀技术和后续扩散处理,制备了AlSiY扩散涂层。同时研究了AlSiY扩散涂层在1000℃下的高温氧化行为和900℃下Na2SO4+NaCl混合盐中的热腐蚀行为。实验结果表明:AlSiY扩散涂层主要由β-NiAl相以及一些弥散分布的α-W、CoWSi相组成。氧化和腐蚀过程中涂层中β-NiAl相提供Al源在表面形成了连续致密的Al2O3膜,使涂层具有很好的抗高温氧化和抗热腐蚀能力。 相似文献
6.
7.
有机防护涂层老化研究进展 总被引:1,自引:1,他引:0
综述了以聚脲及聚氨酯涂层为代表的有机防护涂层在不同测试方法(SEM、AFM、FTIR、EIS、ATR等)和不同试验环境下的耐老化性能,包括有机防护涂层降解老化研究、腐蚀介质在涂层内的渗透性研究、涂层混凝土氯离子渗透性研究、有机涂层的老化研究及电化学阻抗测试研究。研究结果表明:涂层在不同老化条件下表现出不同的老化行为,紫外线/盐雾循环人工加速老化及Cl-在涂层中扩散最终都能导致涂层形貌破坏,防护功能下降;有机涂层附着力丧失及涂层失效程度可用涂层电容(C)值的迅速增加和涂层电阻(R)值的急剧降低为指标进行衡量。 相似文献
8.
《材料保护》2016,(10)
目前对于水在防腐蚀涂层中的传输研究大都集中在静态浸泡条件下,且大部分都基于有机溶剂涂层,鲜见流速对无溶剂涂层在海水中传输行为的影响研究。在60℃的3.5%NaCl溶液中以3种无溶剂环氧防腐蚀涂层自由膜为研究对象,利用称重法(GM)研究了不同流速下水在涂层中的扩散行为,采用差示扫描量热法(DSC)和近红外光谱技术(NIR)研究了水的存在形式以及不同类型水的含量变化。结果表明:胺类固化环氧粉末涂层和酚醛固化环氧粉末涂层在试验流速范围内、酚醛胺固化无溶剂环氧液体涂层在较低流速范围内,水在涂层中的扩散符合FickⅡ模型,而在4 m/s的高流速下,水在无溶剂环氧液体涂层中的扩散偏离FickⅡ模型;随着流体流速增加,3种涂层自由膜的饱和吸水量增加,水在涂层自由膜中的扩散系数变大,涂层自由膜吸水达到饱和的时间减少;水在无溶剂环氧涂层自由膜中有3种存在形式:不形成氢键的水分子(S0)、形成1个氢键的水分子(S1)和形成2个氢键的水分子(S2)。随着流速的增加2种环氧粉末涂层自由膜中S0、S1和S2的含量均增加,水对自由膜的塑化作用增强;而无溶剂环氧液体涂层由于水分子同未反应的环氧基团发生开环反应,使高分子链进一步地交联,导致自由膜内水分含量反而减小。 相似文献
9.
10.
针对过冷水动态制冰过程中过冷却器内易发生冰堵现象,采用纳米氟碳材料对过冷却器表面进行处理,并对纳米氟碳涂层过冷却器进行动态制冰试验研究及性能分析.研究结果表明:水在纳米氟碳涂层表面的接触角可高达163.01°,可有效抑制过冷却器结冰;对比无涂层过冷却器,在过冷水流速为1.95 m/s时,纳米氟碳涂层过冷却器出口过冷度降... 相似文献
11.
Ru-Ti-Ir-Sn氧化物涂层阳极的研究 总被引:8,自引:1,他引:7
采用热分解法制备了不同组分的Ru Ti Ir Sn氧化物涂层阳极 ,从涂层的电化学性能测试和物理性能分析得出 :添加Ir、Sn氧化物 ,虽然提高了电极的耐氧腐蚀 ,但降低了电极的析氯催化活性 ,阳极涂层表面形貌疏松 ,涂层中含有较多的TiO2 (A)相和α Ti相 ,是导致阳极析氯电位升高的主要原因 相似文献
12.
铝合金阳极化氟碳保护涂料的研究 总被引:4,自引:0,他引:4
现有阳极化保护涂料普遍存在耐酸性和弹性差的缺点,为此,采用丙烯酸含氟单体、丙烯酸单体、丁苯橡胶(SBS)通过自由基共聚的方法合成了氟碳树脂,获得了一种耐酸、高弹的铝合金阳极化涂料.对树脂的红外光谱分析表明,丙烯酸含氟单体参与了共聚反应.通过原位共聚的方法引入了纳米二氧化钛.随着氟含量的提高,涂层的耐甲乙酮擦拭性、耐酸性、耐沸水附着力、耐人工老化等性能提高,当氟含量超过6%时涂层的附着力下降;纳米TiO2的引入使涂层的耐盐雾性、抗拉强度明显提高;当固体含量为25%,msbs/m单体=4%时,丁苯橡胶的引入,涂层在柔韧性、伸长率、耐磨性、冲击强度方面均有所提高.氟碳丙烯酸保护涂料能够满足铝合金阳极化绝缘保护的要求. 相似文献
13.
You Jin Kim So Yeon Ko Suji Kim Kyung Min Choi Won-Hee Ryu 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(5):2370030
Surface modification of cathodes using Ni-rich coating layers prevents bulk and surface degradation for the stable operation of Li–ion batteries at high voltages. However, insulating and dense inorganic coating layers often impede charge transfer and ion diffusion kinetics. In this study, the fabrication of dual functional coating materials using metal–organic polyhedra (MOP) with 3D networks within microporous units of Li–ion batteries for surface stabilization and facile ion diffusion is proposed. Zr-based MOP is modified by introducing acyl groups as a chemical linkage (MOPAC), and MOPAC layers are homogenously coated by simple spray coating on the cathode. The coating allow the smooth transport of electrons and ions. MOPAC effectively suppress side reactions between the cathode and electrolyte and protect active materials against aggressive fluoride ions by forming a Li–ion selective passivation film. The MOPAC-coated Ni-rich layered cathode exhibited better cycle retention and enhanced kinetic properties than pristine and MOP-coated cathodes. Reduction of undesirable gas evolution on the cathode by MOPAC is also verified. Microporous MOPAC coating can simultaneously stabilize both the bulk and surface of the Ni-rich layered cathode and maintain good electrochemical reaction kinetics for high-performance Li–ion batteries. 相似文献
14.
15.
16.
17.
18.
B. Rammer Dipl.‐Ing. T. Weber M. Schütze 《Materialwissenschaft und Werkstofftechnik》2008,39(1):29-32
Development of diffusion coatings on nickel base alloys for the use in chlorine‐containing high temperature processes To open up the possibility of using sewage sludge ashes as fertilizers the removal of their heavy metal contents is obligatory. A process newly developed at the BAM Berlin executes this separation in highly chlorine‐containing atmospheres at temperatures of up to 1000 °C [1]. Unfortunately there are no materials available which can withstand such conditions over longer periods of time. This project deals with the development of materials that allow the operation in highly corrosive environments. The corrosion resistance of nickel base alloys against chlorine‐induced high‐temperature corrosion will be optimized by application of aluminum‐ and/or silicon‐containing diffusion coatings. As coating method the pack cementation process was selected. In this process, the metal to be coated is embedded in a powder, consisting of the coating metal, a halogen‐distributor (e.g. ammonium chloride) and aluminum oxide as filler material. During an annealing process of several hours at temperatures of 800 to 1000 °C, gaseous metal halides form. They diffuse through the powder pack and decompose at the substrate surface, thereby depositing the coating metal. Subsequent solid phase diffusion results in the formation of a protective diffusion layer. From the thermodynamic point of view, materials with a high content of aluminum and silicon show best prerequisites to build up slow‐growing, stable oxide layers with a high potential to protect the material against corrosive attacks. The actual performance of the materials will be examined in long‐time tests under simulated field conditions (high temperatures and chlorine‐containing atmospheres). 相似文献