湿法超声机械镀锌-铝层耐蚀性的研究

采用湿法超声机械镀设备制备了Zn-5%Al复合镀层。用多功能扫描电子显微镜及其配备的能谱分析仪观察并分析了复合镀层的形貌及成分,用划格法测试了复合镀层与基体间的结合强度,并用中性盐雾腐蚀试验法测试了复合镀层的耐蚀性。结果表明:湿法超声机械镀Zn-5%Al复合镀层表面平整、结合强度高、耐蚀性好,是一种综合性能优良的防护镀层。     

涂层附着力测试方法分析比较

对现有涂层附着力测试方法(划格法、划叉法、划圈法、拉开法)的差异性进行了分析比较。试验结果表明:划格法、划叉法与划圈法能直观反映涂层附着力,测试结果重复性也较好,但由于测试结果只是以"级"表示,无法提供更精确的量值,存在一定的局限性。采用拉开法进行附着力测试,单试柱法测试结果显著小于双试柱法。单试柱法数据分布范围更窄,标准偏差及数据离散性也较小,测试结果重复性更好。     

涂膜附着力测试的探讨与建议

介绍了拉开法、划格法、划圈法测定涂膜附着力的各标准之间的差异,并重点探讨了拉开法附着力测试中底材、仪器、试验组合、胶粘剂等和划格法附着力测试中切割刀具、胶带等因素对结果的影响,从而对检测条件提出了合理化建议。     

涂装现场检测仪器的使用（Ⅱ）

8 附着力 8．1附着力检测的方法和标准 涂层附着力的检测方法主要有划圈法、划格法、划“×”法和拉开法。不同的检测方法的相应标准见表6。其中划圈法不适用于涂装现场的涂膜附着力检查,只适合于实验室内涂膜性能的检测。     

细长窄深槽类带钩零件环保铬镀层的制备与表征

对细长窄深槽类带钩零件进行电镀，需在槽内壁表面获得完整的电镀覆盖层的同时要求细钩不烧焦，难度相当大，已经成为这类零件生产中长期存在的“瓶颈”环节。针对这一问题，本文以细长窄深槽类带钩零件为基体，制备了环保电镀铬层，并对镀层进行热处理。采用超景深显微镜、扫描电子显微镜（SEM）考察了镀层的外观质量和微观形貌；用能谱仪（EDS）、X射线衍射仪（XRD）分析了镀层的元素组成和相结构；用显微硬度计测试了镀层的显微硬度，并采用划格法检测了镀层与基体的结合力。结果表明：槽内壁表面获得了完整的电镀覆盖层，细钩不烧焦，镀层光亮平滑；镀层与基体结合良好；镀层经热处理后，显微硬度略高于传统工艺制备的镀层硬度。     

提高镀层与基体结合强度的途径

在电镀过程中影响镀层质量的因素很多,生产过程中不可避免地要出现一些质量上的问题,其中镀层与基体的结合强度就是衡量质量的重要指标之一.通过对镀层与基体结合机理及其影响因素的探讨,提出了提高镀层与基体结合强度的途径,为改善镀层的结合力提供了参考依据.     

对电刷镀镀层与基体结合强度机理的探讨

在电刷镀过程中，影响镀层质量的因素很多，实践过程中不可避免地要出现一些质量上的问题。其中镀层与基体金属的结合强度就是衡量镀层质量的重要指标之一。本文通过对镀层与基体电化学结合机理的探讨，提出了提高镀民基体结合强度的途径和方法。     

前处理清洁度对涂装维修后涂层附着力的影响

设计了不同前处理清洁度等级的钢板,并模拟桥梁工程涂装维修工况,用环氧底漆和低表面处理环氧底漆分别制备了标准试样、模拟锈蚀试样、模拟维修试样及模拟维修时返锈试样,采用划格法及拉开法测试了盐雾试验前与盐雾试验144 h和240 h后涂层的附着力,分析了不同试样的附着力变化情况.结果表明,维修涂装前处理清洁度对涂层的附着力有...     

湿法超声机械镀锌–铝层的性能研究

以Q235钢片为基体,采用湿法超声机械镀制备Zn–Al复合镀层。用扫描电子显微镜及其配备的能谱仪分析了锌–铝复合镀层的表面形貌、断面形貌和元素组成,并用测厚仪、贴滤纸法和划格试验分别对镀层的厚度、孔隙率和结合力进行表征。结果表明,湿法超声机械镀Zn–Al复合镀层是由锌粉和铝粉颗粒相互镶嵌、填充所形成的致密堆积体,表面均匀、平整,与基体的结合强度高。镀层主要由锌、铝、锡和铁组成,铝的质量分数低于施镀前混合粉体中铝粉的质量分数。在考虑施镀过程中金属粉的损耗后,所得Zn–Al镀层的厚度满足预定的厚度(30μm)要求。     

螺栓标准件滚镀锌工艺技术研究

采用滚镀工艺在氰化镀锌溶液中电镀标准件螺栓,研究了滚筒的装载量、螺栓螺纹规格及滚筒的转动线速度对镀层的影响。采用X-射线荧光测厚仪对镀锌层的厚度进行测量,采用金相显微镜观察了螺纹的微观形貌,采用划格法对小试块镀锌层的结合力进行了测试,采用中性盐雾试验对螺栓镀锌层的耐蚀性进行了表征。结果表明,镀锌层的外观和结合力良好,可以满足96 h中性盐雾试验没有白锈。     

Optical and mechanical properties of transparent acrylic based polyurethane nano Silica composite coatings

The aim of this work is to investigate the effect of two types of nano Silica (precipitated and fumed) with various concentrations on the optical and mechanical properties of transparent polyurethane acrylic based nano composite coatings. Transparency, gloss, UV absorption, adhesion strength and impact resistance of the samples have been measured. The gloss of the film samples remains unchanged compared to the reference film sample up to 2 wt.% (weight percent) for both types of nanoparticles. The samples containing 4 and 6 wt.% nano Silica show reduction in the gloss property by 4.3% and 5.3%, respectively, for fumed samples and 1.8% and 23% for precipitated samples. The film samples show increase in light absorption in the wavelength region of 250–2000 nm by increasing the content of nano Silica. Also cross cut and pull-off test results show that a good adhesion to steel can be obtained (5B for cross-cut, 7 MPa for pull-off) and no changes in impact strength of the samples with respect to the reference have been observed.     

The effects of zinc aluminum phosphate (ZPA) and zinc aluminum polyphosphate (ZAPP) mixtures on corrosion inhibition performance of epoxy/polyamide coating

The epoxy/polyamide coating was loaded with different pigment mixtures of the zinc phosphate (ZP), zinc aluminum phosphate (ZPA) and zinc aluminum polyphosphate (ZAPP) pigments. The electrochemical impedance spectroscopy (EIS) and salt spray test were used to investigate corrosion inhibition performance of the coatings. The adhesion strengths of the coatings were measured by a pull-off test. Results revealed lower coating pull-off strength loss when the ZPA and ZAPP pigments were used. A significant decrease in number of blisters together with low pull-off strength loss and best corrosion inhibition properties were observed when the mixture of 80:20 of ZAPP:ZPA was used.     

Effect of a coupling agent on the adhesion of paint to timber

A method of treating timber before applying a coating has been developed and tested. An organofunctional silane coupling compound was found that was capable of reacting and forming bonds with both wood and a range of coatings. Wet and dry adhesion strength between a range of coatings and wood has been determined by the direct pull-off test under a variety of test conditions. The data presented show how the bridging of the interface between wood and coating can, with some coatings, improve not only the initial bond strength but also provide significantly higher wet adhesion strength and long-term bond durability.     

Measuring the coating adhesion strength of electrodes for lithium-ion batteries

The coating adhesion strength of lithium-ion battery electrodes is a very important mechanical property, affecting the electrochemical life time of battery cells and the electrochemical handling during cell manufacturing. Hence the establishment of a standardized pull-off test with high reproducibility was long time overdue. The measurement setup is realized in a material testing machine. Machine and process parameters have been investigated to propose a reliable measurement procedure with a clearly specified parameter setup. Data acquisition rate (f), contact stress (σ_c), dwell time (t_d) and pull-off velocity (v_po) were identified to affect the adhesion strength measurement significantly. Finally electrodes with material and process parameter variations were manufactured to assess the applicability of the presented method. The impact of the amount of binder and its molecular weight as well as the influence of the dry mixing and the dispersing process on adhesion strength was verified and the differences can be clearly distinguished by the developed test method.     

新型风电塔筒涂膜镀锌的制备及性能研究

通过对涂膜镀锌溶剂体系的筛选和锌粉含量的调整,并采用耐盐水性测定、中性盐雾试验和导电性测试等方法对自制的涂膜镀锌进行了耐腐蚀性研究。结果表明:当溶剂体系中醋酸丁酯与重芳烃质量比为3∶1时,涂料具有良好的机械性能、表面状态和干燥时间;当干膜中锌粉含量为96%时,涂层防腐性能最佳,且性价比高,适用于重防腐领域;导电性测试表明:涂膜镀锌与普通富锌涂料相比,具有更为优异的电化学性能,能够起到良好的阴极保护作用。     

粉尘对风电叶片涂层附着性能的影响

风电叶片在生产过程中,复合材料表面会由于各种原因粘附有粉尘.在叶片的涂装过程中,粉尘的存在会对漆膜在复合材料壳体上及漆膜层间的附着性能产生负面影响.该研究设计实验,使叶片壳体或涂层表面沉降粉尘后进行下道涂装,涂层固化后通过拉开法考察了涂装过程中粉尘对漆膜附着性能的影响.结果表明:粉尘的存在对涂层对复合材料壳体及涂层层间...     

Evaluation of Adhesion Improvement of a GFRP Treated with Atmospheric Plasma Torch

The applications (and repair) of glass fiber reinforced epoxy composites are increasing in different industries (wind turbines, boats, chassis of buses, etc.) due to specific strength and low cost. Their major disadvantage is the difficulty to shape complex components. This problem can be solved manufacturing different parts, being adhesively bonded afterwards. This work studies the effect of atmospheric pressure plasma torch compared to grit-blasting to improve adhesion. After surface treating different parts, the changes of wettability and surface energy were measured. Treated samples were bonded with polyurethane and epoxy adhesives, and the quality of the bond was evaluated using pull-off adhesion tests and fracture strength test under cleavage loads. Obtained results allow to select the most adequate treatment in terms of mechanical requirements.     

Micro-scratch test for adhesion evaluation of thin films

In tribological applications, surface properties govern performance, and hence the utilization of coatings to tailor properties has become an essential component of materials technology. The most critical requirement for such coatings is adequate adhesion. Therefore, the need to measure coating/substrate interfacial strength and to characterize the factors influencing it is critical. However, the most common method currently used to characterize adhesion-the scratch test-is inadequate because it does not really measure adhesion. It is indicative of a relative measure of coating durability, which can be useful, at best, for quality control purposes. Consequently, the need for a test that can more accurately determine the adhesion characteristics of thin films is imperative. The development of a micro-scratch test and how it addresses some of the deficiencies of the conventional scratch test are discussed.     

玻璃钢/典型涂层体系失效研究

研究了影响典型涂层与玻璃钢附着力的影响因素,包括表面预处理方法、涂层种类等。研究表明:玻璃钢/涂层附着力与涂层中主要官能团的极性有关。     

Adhesion of gold and copper thin films deposited on alumina and magnesium oxide

Scratch and pull-off methods for adhesion measurement were applied to various film/ substrate systems. The film crystallographic structure was investigated by transmission electron microscopy (TEM) in order to correlate it to the adhesion strength. We also correlate the film and substrate electronic structures (in particular the electronegativity) to the adhesion strength. The results of adhesion measurement are also discussed with respect to the substrate temperature. The main results are that the adhesion strength is greater when the film is deposited on magnesium oxide than on alumina substrates, and for the copper than for the gold deposit. Also, the adhesion strength increases with the substrate temperature.