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Chinese Chemical Letters 2009年第7期20卷 845-848页

作者： Xiao Wei Zhou Hui Ming Jin Lin Nan Zhang College of Mechanical Engineering Yangzhou University Yangzhou 225009 China College of Environmental Science and Engineering Peking University Beijing 100023 China

Three kinds of Ni-P electroless coatings were prepared in nickel sulphate solution at different pH values of 4.5, 5.5 and 6.5 with the purpose of ascertaining the influence of pH value on microstructure, internal stress statue and thermal stability of the coatings. Laser curvature （LC） method was used to measure the residual stress level in the coatings. Scanning electronic microscopy （SEM） and transmission electronic microscopy with energy dispersive spectrum （TEM/EDS） were used to examine the surface morphology and internal phase structure of the coatings, respectively. Differential scanning calorimeter （DSC） was used to analyze the phase transformation and thermal stability of the coatings at high temperature. Results showed the NiP coating prepared at pH 5.5 with nanocrystal mixed in amorphous structure had the worst thermal stability. The relatively higher stability of Ni-P coatings prepared at pH 4.5 and 6.5 was ascribed to the lower tensile stress level and much finer grain size, respectively. Besides, inverse Hall-Petch effect of annealing strengthening might also contribute to the integrity of NiP coating prepared at pH 6.5. C 2009 Hui Ming Jin. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Microstructure Stress electroless Ni-P

Influence of electroless Sn/Bi on Sn/Pb soldered joint strength

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中国有色金属学会会刊：英文版 2005年第S3期15卷 349-352页

作者：禹胜林朱小军严伟 Nanjing Research Institute of Electronics Technology Nanjing 210013 China

The solder joint strength of Pb/Sn soldering aluminum with electroless layer Sn/Bi and Cu was studied. The results show that the joint shear strength of electroless Sn/Bi on aluminum surface is lower than that of Cu. A Pb-riched region with porosity is formed in region of soldering fillet with electroless Sn/Bi. Both the electroless Sn/Bi layer and Pb-riched layer become thicker, which are the reasons why the shear strength of the solder joint with electroless Sn/Bi on aluminum surface is lower than that of electroless Cu, and the higher the thickness of the electroless Sn/Bi layer is, the lower the shear strength of solder joint is.

关键词： electroless layer soldered joint Sn/Pb Sn/Bi shear strength

Enhanced Thermoelectric and Mechanical Properties of n-type Bi2Te2.7Se0.3 Bulk Alloys by electroless Plating with Cu

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Journal of Wuhan University of Technology(Materials Science) 2019年第4期34卷 840-844页

作者： DAI Xueting HUANG Zhongyue ZU Fangqiu State-owned Machinery Factory in Wuhu Wuhu 241007China School of Materials Science & Engineering Hefei University of TechnologyHefei 230009China

Bi2Te2.7Se0.3/Cu core/shell powders were prepared by electroless plating and hydrogen reduction, and then sintered into bulk by spark plasma sintering in order to improve the thermoelectric and mechanical properties of n-type Bi-Te thermoelectric material. After electroless plating, with the increasing of Cu content, Seebeck coefficient keeps increasing and power factor enhances significantly. The highest power factor increases by three times and reaches 23.8 W·cm^-1·K^-2 at room temperature in Bi2Te2.7Se0.3 with 0.22 wt%Cu sample, which means electrical transport properties of Bi2Te2.7Se0.3/Cu samples have been ***, the ZT values of Bi2Te2.7Se0.3/Cu samples can be enhanced at different temperature zone by adjusting the Cu content. Bi2Te2.7Se0.3 with 0.05 wt% Cu sample has the best thermoelectric properties in high temperature zone, and the ZT peak value increases from 0.35 to 0.85 at 623 K. When the Cu content increases to 0.15 wt%,the ZT peak value moves to the low temperature(373 K) and increases from 0.24 to 0.71. At the same time, the mechanical properties increases with the increasing of Cu content.

关键词： thermoelectric materials electroless plating thermoelectric properties mechanical properties

Study on the Technology of Ni-P electroless Plating on the Mg Alloy

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稀有金属材料与工程 2012年第S1期41卷 472-474页

作者： Liu Yihan Sun Huawei Jiang Yanan Northeastern Univ Shenyang 110004 Peoples R China Shenyang Second High Sch Shenyang 110016 Peoples R China

Base on the analysis for the corrosion mechanism of the Mg alloys,the technology of Ni-P directly electroless plating on the Mg-10Li-1Zn alloys was *** effects of the pre-treatment on the morphologies of substrate and plating films were investigated,The result shows that Ni-P electroless plating could be divided two steps:the induction period and the rapid deposition *** Ni-P film is amorphous structure:A excellent Ni-P coating can be obtained under the optimal *** Ni-P coating can obviously improve the corrosion resistance of Mg alloy in variety environment.

关键词： Mg alloy electroless plating Ni-P coating corrosion protection

Study of the electroless Silver Seed Formation on Silicon Surface

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Chinese Journal of Chemistry 2007年第2期25卷 208-212页

作者：佟浩王春明叶为春常延龙力虎林 College of Meterial Science and Technology Nanjing University of Aeronautics & Astronautics Nanjing Jiangsu 210016 China Department of Chemistry Lanzhou University Lanzhou Gansu 730000 China

The silver seed on silicon was prepared through aqueous I-IF and AgNO3 solution at room temperature. In order to explore the formation process of silver seed on silicon, the methods of open circuit potential with time （OCP-t）, anodic stripping sweep voltammetry （ASV） and scanning tunneling microscope （STM） were used in this work. The procedure of silver nucleus growing into large particles was explained by electro-negativity. The growth mechanism of silver seed on silicon has been presented： at first, the silver monolayer and multilayer firstly grows onto silicon without fully covering the surface at the expense of silicon etching due to the silver seed attracting the electron from silicon, after that, the monolayer coalesces together, forming continuous grain film with some silver atoms diffusing into the silicon and the multilayer still grows thick simultaneously.

关键词： electroless silver seed monolayer silicon

Removal of nickel from spent electroless nickel-plating bath with nickel foam cathode

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Journal of Harbin Institute of Technology(New Series) 2002年第4期9卷 332-335页

作者：于秀娟郑彤魏杰周定 Dept.of Environmental Engineering and Science

The electrochemical method was used to remove nickel ion from spent electroless nickel plating bath (pH=5 3). An electrolytic cell was composed of a porous nickel foam cathode and an inert RuO 2/Ti anode. Nickel ions were reduced and deposited on the surface of the nickel foam cathode. The effect of current density (i), linear velocity of wastewater(v), gap between cathode and anode(d C/A) and reaction time(t) on nickel removal rate and current efficiency were studied. As reaction time prolonged, nickel removal rate increased while current efficiency decreased. And larger v and smaller d C/A can enhance nickel removal rate and increase current efficiency by promoting mass transfer and dropping concentration polarization. The effect of current density on nickel removal by electrochemistry was related to other parameters. After three hours’ electrolysis with i=1 0 A/dm2, v=18 5 cm/min and d C/A=0 5 cm, nickel removal rate and current efficiency reached 85 6% and 29 1%, respectively.

关键词： spent electroless nickel plating bath electrochemical treatment nickel foam cathode

CATALYTIC ACTIVITIES OF SUBSTRATE METALS IN A Ni-B-SiC electroless COMPOSITE BATH

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中国有色金属学会会刊：英文版 1993年第2期3卷 36-40页

作者： Yu,Xinwei Anshan Institute of Iron and Steel Technology,Anshan 114002,ChinaZhao,Guopeng University of Science and Technology Beijing,Beijing 100083,ChinaWang,Fengyin Wang,Guobin Northeast University of Technology,Shenyang 110000,China

The catalytic activities of different substrate metals in Ni-B-SiC electroless composite bath was investigatedby means of measuring stationary potentials,potential-time curves and *** mechanism of electrolessplating taking place in the substrate metals at initial stage was *** results showed:(1)Inaddition to the stationary potential of the substrate metal and the temperature of the bath,the change of the sur-face state of metal,e.g.,its passivity,is one of the factors for deciding catalytic activity of a substrate metal.(2)the transition time is helpful in determines the degree of catalytic activity.(3)If the substrate metals possesscatalytic activity,the coating rates of electroless plating are mostly equal.

关键词： electroless pIating substrate metals stationary potential catalytic activity passivity

HARDNESS AND WEAR RESISTANCE OF electroless NICKEL DEPOSITS

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中国有色金属学会会刊：英文版 1998年第4期8卷 111-116页

作者： Zhang Yongzhong, Zhang Kui, Fan Jianzhong and Zhang Shaoming General Research Institute for Nonferrous Metals, Beijing 100088, P. R. China Yao Mei School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. Chi

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关键词： electroless Ni 1.5%P deposit Ni 10.5%P deposit hardness wear resistance

THE STUDY OF electroless NICKEL ACCELERATING AGENT

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 1002-1006页

作者： Q. Zhang, S. Guan and S.M. Li Beijing University Of Aeronautics And Astronautics, Beijing 100083, China

The effects of accelerating agent on the deposition speed of electroless Nickel Plating, the stability of solution and the corrosion resistant of The EN coatings were studied. The influence of A1 content on EN activation energy, the rest potential and polarization cures are measured. The mechanism of the acceleration effect of A1 on the EN plating was proposed.

关键词： electroless nickel plating accelerating agent

electroless Plating of Palladium Membranes on Porous Substrates for Hydrogen Separation and the Effects of Process Factors on Plating Rate and Efficiency: A Review

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Journal of Power and Energy Engineering 2020年第2期8卷 1-19页

作者： Abubakar Alkali Centre for Process Integration & Membrane Technology School of Engineering Robert Gordon University Aberdeen UK Department of Petroleum and Natural Gas Engineering Baze University Abuja Nigeria

The electroless plating of palladium and palladium alloy membranes is fast becoming an important and enabling technology. This is more so when juxtaposed with the rising demand for high purity hydrogen for applications particularly in proton exchange membrane fuel cells (PEMFC). The effect of process factors such as sensitization and activation during surface modification, concentration of the reducing agent, plating temperature, time, pH, additives, air aeration on plating efficiency, quality of the palladium film and deposit morphology is reviewed with the aim of identifying areas requiring further investigation. The paper also reviews how these process factors could be optimised for better plating efficiency and overall membrane quality. The concentration of the reducing agent has been identified as the limiting factor on plating efficiency albeit other process factors separately impact on the plating efficiency. Furthermore, bulk precipitation caused by concentration of the reducing agent has been identified as a major problem during electroless plating with hydrazine based plating baths. To ameliorate this problem, a multi step addition of the hydrazine reducer in separate portions has been recommended.

关键词： electroless Plating Hydrogen Palladium Membranes Plating Efficiency Process Factors