化学镀银导电涤纶织物的研究

以葡萄糖为还原剂,采用化学镀银法制备导电涤纶织物,研究了硝酸银浓度、葡萄糖浓度、乙醇浓度及反应时间对涤纶织物导电性能的影响,通过SEM和XRD图谱分析导电织物表面形貌与晶体结构,并测试其电磁屏蔽性能。结果表明,化学镀银涤纶织物具有优异的导电性能,且化学镀银后涤纶织物的电磁屏蔽性能明显增加。     

Effect of carbon fibre on properties of TiB2/C composite cathode coating for aluminum electrolysis

The tensile strength, compressive strength and electrical resistivity of TiB2/C composite cathode coating were measured with a hydraulic pressure universal test machine and an electrical resistivity test device, and the effects of carbon fibre content and carbon fibre length on tensile strength, compressive strength and electrical resistivity were investigated. The results show that the tensile strength of coating increases at the beginning and then reduces with the increase of carbon fibre content when the carbon fibre (length of 3 mm) content ranges from 0 to 4.0%; at the carbon fibre content of 1.5%, the tensile strength of coating reaches the maximum, 25.6 MPa. For the coating with carbon fibre content of 1.5%, the carbon fibre length has a great influence on tensile strength and compressive strength of coating; when the carbon fibre length is 6 mm, the tensile strength and compressive strength of coating reach the maximum, 27.6 MPa and 39.2 MPa, respectively. The electrical resistivity of coating reduces with the rise of temperature and the length of carbon fibre, and the influence of carbon fibre length on electrical resistivity of coating at low temperature (30-200℃) is more obvious than that at high temperature (960℃).     

Electroless copper-phosphorus coatings with the addition of silicon carbide （SiC） particles

Cu-P-silicon carbide(SiC)composite coatings were deposited by means of electroless plating.The effects ofpH values,temperature,and different concentrations of sodium hypophosphite(NaH2PO2·H2O),nickel sulfate(NiSO4·6H2O),sodium citrate(C6H5Na3O7·2H2O)and SiC on the deposition rate and coating compositions were evaluated,and the bath formulation for Cu-P-SiC composite coatings was optimised.The coating compositions were determined using energy-dispersive X-ray analysis(EDX).The corresponding optimal operating parameters for depositing Cu-P-SiC are as follows:pH 9; temperature,90℃; NaH2PO2·H2O concentration,125 g/L; NiSO4·6H2O concentration,3.125 g/L; SiC concentration,5 g/L; and C6H5Na3O7·2H2O concentration,50 g/L.The surface morphology of the coatings analysed by scanning electron microscopy(SEM)shows that Cu particles are uniformly distributed.The hardness and wear resistance of Cu-P composite coatings are improved with the addition of SiC particles and increase with the increase of SiC content.     

碳纳米管表面化学镀Ni的研究

研究了在碳纳米管表面化学镀Ni的新方法．在一定条件下，不通过敏化活化处理，运用“诱发”反应活化法，在碳纳米管表面获得致密均匀的Ni镀层．     

ZrO2陶瓷表面化学镀镍

研究了ZrO2陶瓷化学镀镍特殊的前处理工艺．对还原剂的浓度、络合剂的种类及浓度、pH值以及温度等因素对镀速和镀层中的含磷量的影响进行了探讨，并对镀层的性能以及微观形貌和结构进行了分析。结果表明，在该文工艺条件下能在ZrO2陶瓷表面获得细致均匀、结合力和耐蚀性能良好的化学镀镍层。     

纳米螺旋碳纤维表面金属涂层的制备

研究了在铁片试样上化学镀镍铁合金涂层的工艺,考察了主盐、还原剂对化学镀反应沉积速率的影响。利用此工艺在经过敏化、活化处理后的纳米螺旋碳纤维表面沉积出Ni-Fe-P合金涂层。采用能量色散X射线谱(EDS)分析得出涂层成分,利用扫描电子显微镜(SEM)观察涂层形貌。结果表明,可以在纳米螺旋碳纤维表面沉积连续、均匀的合金涂层。     

化学镀Ni-P合金镀液的稳定性研究

镀液的稳定性是影响化学镀的成本．镀层质量、使用寿命和能否产业化等问题的重要因素。本文主要研究稳定剂、络合剂以及pH值和温度对镀液稳定性的影响规律，对化学镀过程的控制有一定的参考作用。     

涤纶织物化学镀镍铜合金研究

采用化学镀技术,实现了涤纶织物表面镍铜合金镀,借助SEM、EDX对镀层表面形貌、成份进行了分析,并对化学镀织物的电磁波屏蔽效能、表面比电阻和拉伸性能进行了测试。结果表明,随着增重率的增加,电磁波屏蔽效能开始时增加较快,后又趋于平缓,当增重率基本接近时,屏蔽效能主要受金属镀层成份和致密性的影响。表面比电阻随着增重率的增加而减小。化学镀织物的拉伸曲线同时具有金属和纤维的拉伸特性,主要受金属镀层厚度的影响。     

化学镀非晶态Pd膜制备工艺的优化研究

采用化学镀方法施镀可获得致密吸附性好的单颗粒钯膜.通过对比不同试验条件,对化学镀钯膜的过程中所涉及到的工艺条件,包括施镀温度、施镀时间、pH值进行优化,结合SEM、XRD、EDS等分析手段对实验所得钯膜进行表征.实验表明,在温度为70 ℃,施镀时间2 h,NH4OH的浓度4.5 mol/L,pH值9.8的施镀条件下,得到膜厚约为0.6 μm非晶态合金镀层,具有良好的导电性、抗腐蚀性和硬度,结构致密不易破损脱落,并且其成分较纯,不含其它杂质.     

Electromagnetic Interference Shielding Properties of Electroless Nickel-coated Carbon Fiber Paper Reinforced Epoxy Composites

Carbon fibers(CFs) were coated with a nickel-phosphorus(Ni-P) film using an electroless plating process. The morphology, elemental composition and phases in the coating layer of the CFs were investigated by scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and X-ray diffraction(XRD), respectively. Wet paper-making method was used to prepare nickle coated carbon fiber paper(NCFP). Vacuum assisted infusion molding process(VAIMP) was employed to manufacture the NCFP reinforced epoxy composites, and carbon fiber paper(CFP) reinforced epoxy composites were also produced as a comparison. Electromagnetic interference(EMI) shielding properties of the composites were measured in the 3.22-4.9 GHz frequency range using waveguide method. Both NCFP and CFP reinforced epoxy composites of 0.5 mm thickness exhibited high EMI shielding effectiveness(SE) at 8wt% fiber content, 35 d B and 30 d B, respectively, and reflection was the dominant shielding mechanism.     

Preparation of copper-coated fine molybdenum powders with electroless technique

The molybdenum powders with average particle size of 3 μm were coated with copper by electroless plating. The influence of pretreatment,solution composition and plating conditions on electroless copper plating was studied. The copper-coated molybdenum powders were examined by SEM and XRD. Results indicate that a series of optimization methods is used to add activated sites before electroless copper plating. Taking TEA and EDTA as chief and assistant complex agents respectively,2,2’-bipyridyl and PEG as double stabilizers,the Mo powders are coated with copper successfully with little Cu2O contained,at the same time,Mo-Cu composite powders with copper content of 15-85 wt% can be obtained. The optimal values of pH,temperature and HCHO concentration are 12-13,60-65 ℃ and 22-26 mL/L,respectively.     

碳纳米纤维／镍管复合材料的制备

采用化学镀法在化学纤维布表面覆盖均匀镍层,通过热处理去除基体后获得中空镍纤维管;将其置于化学气相沉积装置中,通过调整合适的氢气和甲烷流量比及气压条件制备了以中空微米镍纤维管为主体结构、碳纳米纤维（CNF）以及金属管体结构为存储介质的碳纳米纤维／镍管复合纤维材料．运用扫描电子显微镜（SEM）分析中空镍纤维及复合纤维管表面形貌,x射线衍射（XRD）对复合纤维管晶相组成进行表征．结果表明,利用模版法制备出的中空镍纤维管孔径在10μm左右,管壁厚约0．5μm;化学气相沉积制备过程中,当微波功率500W,氢气和甲烷流量比100：6,气压4．0kPa,沉积时间5min时,复合纤维管外壁和端口内壁均匀沉积长径比较大且直径均匀分布的碳纳米纤维,碳纤维直径约50nm;复合纤维成分为碳纳米纤维、镍和三镍化磷合金相,其中碳纳米纤维表现为石墨相．表面覆盖有碳纳米纤维的镍管复合材料,增加了材料自身的吸附存储和导电性能,可应用于多相催化、电容存储和电极材料等领域．     

阴极脉冲电流作用下的Ni－P合金化学镀过程

研究了Ｍｉ－Ｐ合金脉冲化学镀过程，找出了镀层Ｐ含量，镀速和脉冲电流参数，温度的关系。由于脉冲电流的作用，可以减缓镀液中亚磷酸盐的积累，并且Ｐ的化学沉积过程也得到加速。     

Fabrication of W@Cu composite powders by direct electroless plating using a dripping method

A direct electroless copper (Cu) coating on tungsten powders method requiring no surface treatment or stabilizing agent and using glyoxylic acid (C₂H₂O₃) as a reducing agent was reported. The effects of copper sulfate concentration and the pH of the plating solution on the properties of the prepared W@Cu composite powders were assessed. The content of Cu in the composite powders was controlled by adjusting the concentration of copper sulfate in the electroless plating solution. A uniform, dense, and consistent Cu coating was obtained under the established optimum conditions (flow rate of C₂H₂O₃ = 5.01 mL/min, solution pH = 12.25 and reaction temperature 45.35 °C) by using central composite design method. In addition, the crystalline Cu coating was evenly dispersed within the W@Cu composite powders and Cu element in the coating existed as Cu0. The formation mechanism for the W@Cu composite powders by electroless plating in the absence of surface treatment and stabilizing agent was also proposed.     

化学镀镍中络合反应的热力学过程分析

建立了化学镀镍中多元酸性络合剂与镍盐络合过程的热力学通式模型。以吉布斯自由能ΔG值为判据,通过该模型分别对乳酸、琥珀酸、硼酸和焦磷酸等4种络合剂的络合过程进行了热力学计算和影响因素分析。结果表明,在一定的条件下,ΔG值与pH值成正比,与温度(ΔG≤0时)和络合率成反比,与络合剂电离常数和元数的相互约束有关。在温度65~95℃和络合率65%~99%范围内,当ΔG=0时,使用上述4种络合剂的镀液pH值应分别小于4.9~6.6、5.4~6.2、12.4~12.9和5.2~5.7。     

纳米粒子对复合化学镀镍层性能的影响

在化学镀镍溶液中添加银纳米粒子,在钢铁基体上制备Ni-P／Ag纳米复合镀层。研究了添加银纳米粒子前后镀液的镀速、镀层的厚度、镀态和热处理态的硬度变化,分析了银纳米粒子对镀层性能的影响。研究结果表明,银纳米粒子使得镀层的沉积速率加快,厚度增加,硬度提高。镀层的表面形貌也由于银纳米粒子的存在而发生了改变。     

Mechanism and Microstructure of Electroless Ni-Fe-P Plating on CNTs

Electroless Ni-Fe-P alloy plating on the surface of CNTs was carded out with a bath using citrate salt and lactic acid as complex agents. We proposed a chemical reaction mechanism. The morphology, structure and chemical composition of the Ni-Fe-P/CNTs were studied with the aid of a scanning electronic microscope （SEM）, X-ray diffraction （XRD） and an energy-dispersive X-ray spectral analysis （EDS）. The results show that through a correct pre-treatment and electroless plating, Ni-Fe-P/CNTs composite particles can be obtained. The optimum electroless plating parameters of 35-42℃ and pH of 8.5-9.7 were achieved. The as-plated Ni-Fe-P alloy is amorphous. After a heat treatment at 500℃ for 90 min in H2, the coating is transformed into crystalloid Ni3E Fe2NiP and （Fe,Ni）3R The Ni-Fe-P alloy coating on the surface of CNTs is smooth and unique. The amount of Ni on the surface （mass fraction） of the Ni-Fe-P/CNTs composite particles is 29.13%, that of Fe 3.19% and that of P 2.28%.     

导电聚苯胺的合成及对电磁屏蔽涂料屏蔽效能的影响

用盐酸作掺杂剂合成电导率达15S／cm的导电聚苯胺,讨论氧化剂的用量、盐酸的浓度、反应时间、反应温度等因素对聚苯胺（PAn）导电性的影响,并得到了最佳实验条件：氧化剂：苯胺：盐酸=1：2：4,盐酸浓度1mol／L,反应温度0℃,反应时间4h。此外,测试结果表明,在体积分数为10％Ni的导电涂料中加入5％所制的导电聚苯胺后,涂料的屏蔽效能显著提高,这是形成了更多有利于电子运动的导电网络所致。     

镁合金化学镀及其添加剂研究

精选镁合金化学镀的前处理工艺和镀镍液配方,根据该工艺得到的镀层试验检测表明:该合金具有耐腐蚀性强、硬度高、结构致密、光泽性好,且有一定延展性;并通过实验比较了4种添加剂对镁合金化学镀镀速及镀液稳定性的影响,实验结果表明,钇和铕对镀液的稳定性影响较大,氟化铵和碳酸钠对镀速的影响较为显著,尤其是添加的Y3 浓度为0.02 g/L时,镀液的稳定性提高最多,而碳酸钠在19 g/L左右时加速作用最为明显.文中并分析了它们的影响机理.     

Growth behavior of electroless copper on silicon substrate

The growth behavior containing deposit morphology, growth rate, activation energy, and growth mechanism of copper on silicon substrate, especially at the initial stage, in the electroless plating process was studied. Copper was deposited on the surface of the silicon substrate in an electloless plating bath containing formalin （CH2O 37vol%） as a reducing agent at a pH value of 12.5 and a temperature of 50-75℃. The copper deposit was characterized using a field emission scanning electron microscope and transmission electron microscope. The results showed that after the activation process, nanoscale Pd particles were distributed evenly on the surface of the silicon; in the deposition process, copper first nucleated at locations not only near the Pd particles but also between the Pd particles; the growth rate of electroless Cu ranged from 0.517 nm/s at 50℃ to 1.929 nm/s at 75℃. The activation energy of electroless Cu on Si was 52.97 kJ/mol.