AgC.docx

1、AgC银石墨2-5%的银石墨触头最主要的特性是抗熔焊高可靠性，低的接触电阻，温升小，作为滑动触头使用时有自润滑性能等，典型使用在低压断路等、电抗保护开关、线路保护开关、漏电保护开关和滑环转换器等采用烧结挤压工艺制造的银石墨触头材料，不仅致密化程度高，而且由于石墨质点呈纤维取向，更有利于在电弧作用下烧损率减少与Cu、AgNi配对使用。途：作为弧触最大的应用领域是低压断路器，线路保护开关，故障电流保护开关，滑动电刷以及铁道信号继电，对许多应用场合，重量的石墨含量即可，在苛刻通断条件下，含量可到量比例 特性：导电性能好，接触电阻低，抗熔焊性高，在短路电流下也不会熔焊，滑动性能好，但电损蚀大，灭弧能力

2、较差，在电弧的较长时间作用下，烧损剧烈，使灭弧罩积碳，脆弱和较难焊接AgC触头材料性能特点及应用材料名称性能特点主要应用领域供货形式银石墨 （AgC）用挤压法制造的AgC材料中C成纤维状分布。由于C的脆性，使AgC成为所有触头材料中抗动熔焊性最好的材料。而且AgC的接触电阻较低广泛应用于保护断路器中，通常与细晶银、银镍或铜非对称配对使用片材AgC触头产品机械物理性能工艺方法产品形状状态抗拉强度MPa延伸率%密 度g/cm3 电阻率cm硬度（HV） AgC4/Ag-MSE-T挤压片材退火/8.952.0943 - 50AgC3/Ag-SS-T模压片材退火/9.402.3246 - 56金相图片A

3、gC4/Ag-MSE-T200XAgC3/Ag-SS-T100X石墨粉镀银新工艺研究【英文篇名】STUDY ON PROCESS OF SILVER ELECTROPLATING ON GRAPHITE POWDERS【作者中文名】丁国芸; 夏金童; 肖勇; 李闯; 高守磊;【作者英文名】DING Guo-yun; XIA Jin-tong; XIAO Yong; LI Chuang; GAO Shou-lei（College of materials Science and Engineering; Hunan university; Changsha 410082; China）;【作者单

4、位】湖南大学材料科学与工程学院; 湖南大学材料科学与工程学院 湖南长沙; 湖南长沙;【文献出处】炭素技术, Carbon Techniques, 编辑部邮箱 2007年 05期期刊荣誉：ASPT来源刊CJFD收录刊【关键词】石墨粉; 惰性阳极; 无氧镀银; 含银量;【英文关键词】Graphite powders; inertia anode; cyanide-free silver plating; silver content;【摘要】研究了镀液中硝酸银浓度、石墨粉加入量和阴极电流密度等工艺条件对镀银石墨粉含银量和电镀效果的影响。用扫描电镜对镀银石墨粉的微观形貌和镀覆效果进行分析,通过X射线

5、衍射仪对镀银石墨粉高温灼烧后的剩余物进行分析测试并计算镀银石墨粉的含银量。研究结果表明:采用惰性电极作为电镀阳极,在化学镀预处理过的石墨粉表面可成功镀覆一层银,其含银量达76%。【英文摘要】The effects of AgNO3 concentration,the amount of graphite powders and cathode efficiency on silver content and electroplating effect of the silver electroplating graphite powders were analyzed in detail.Th

6、e microstructure of silver-plated graphite powders was characterized and analyzed by SEM.The remains of silver-plated graphite powders sintered at high temperature were analyzed through X-ray diffraction and the silver content was obtained.The results show that by using inert anode as positive pole,

7、a fine .【DOI】另外，银对石墨的润湿性不好，导致烧结后的银-石墨复合材料界面结合强度低，材料承受载荷时往往造成银和石墨之间的剥离。制备性能优良的银-石墨复合材料的关键是改善石墨与银的润湿性，有效方法之一是在石墨粉表面镀银，然后压制烧结成银-石墨复合材料。.Electroless plating of silver on graphite powders and the study of its conductive adhesiveTongxiang, Liang (Institute of Nuclear and New Energy Technology, Tsinghua Un

8、iversity); Wenli, Guo; Yinghui, Yan; Chunhe, Tang Source: International Journal of Adhesion and Adhesives, v 28, n 1-2, January, 2008, p 55-58ISSN: 0143-7496 CODEN: IJAADK Publisher: Elsevier Ltd Abstract: In this paper, silver plating graphite powders were developed by electroless plating method. T

9、he density of silver plating graphite powders was 2.61 g/cm3 and the ratio of silver for the powders was 25 wt%. After being mixed with epoxy resin and curing agent, silver plating graphite powders conductive adhesive was obtained, with the percolation concentration of 28 vol%. Compared to pure Ag c

10、onductive adhesive, the new conductive adhesive has the advantage of low cost. Adhesives based on the graphite or Ag plating graphite powders exhibited higher tensile strength and larger failure elongations than pure Ag conductive adhesive. 2007 Elsevier Ltd. All rights reserved. (7 refs.)Ei control

11、led terms:Silver plating - Adhesives - Electroless plating - Epoxy resins - Failure analysis - Graphite - Tensile strengthUncontrolled terms:Graphite powders - Conductive adhesiveClassification Code: 421 Strength of Building Materials; Mechanical Properties - 482.2 Minerals - 539.3 Metal Plating - 5

12、39.3.2 Electroless Plating - 547.1 Precious Metals - 804.1 Organic Compounds - 815.1.1 Organic PolymersDatabase: CompendexDevelopment of new silver plated graphite powders used as conductive fillersmore optionsAuthor(s): Qu Zhan-min Source: Electroplating & Finishing Volume: 26Issue: 9Pages: 14-17Pu

13、blished: September 2007Abstract: After oxidation treatment, the flake graphite powders were electrolessly copper plated followed by electroless silver plating. The process specifications were presented, the influential factors were analyzed and the deposit performances were tested. The results show

14、that the silicone rubber with the addition of silver plated graphite powders has the volume resistivity of 2.0 * 10 -4 Omega ldr cm and shielding effectiveness of 75 dB in the low-frequency region, and it is a kind of good conductive filler for electromagnetic shielding. Accession Number: 9793928 Do

15、cument Type: Journal Paper Language: Chinese Treatment: Experimental Controlled Indexing: electroless deposition; electromagnetic shielding; electroplated coatings; graphite; oxidation; powders; silver Uncontrolled Indexing: silver plated graphite powders; conductive fillers; oxidation treatment; fl

16、ake graphite powders; electroless silver plating; silicone rubber; electromagnetic shielding; resistivity 0.0002 ohmcm; Ag-C; C Classification Codes: A6140G Structure of powders and porous materials; A8160 Corrosion, oxidation, etching, and other surface treatments; A8115L Deposition from liquid pha

17、ses (melts and solutions) Numerical Data Indexing: resistivity 2.0E-06 ohmm Chemical Indexing: AgC/ss Ag/ss C/ss AgC/bin Ag/bin C/bin; C/sur C/el Author Address: Qu Zhan-min; Meiwu Paper Ind. Co. Ltd., Xian, China Publisher: Editorial Department of Electroplating and Finishing, China Number of Refer

18、ences: 4 CODEN: DYTUEM Electroless plating of silver on graphite powders and the study of its conductive adhesive Liang Tongxiang, a, , Guo Wenlia, Yan Yinghuia and Tang ChunheaaInstitute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China Accepted 14 March 2007. Availab

19、le online 31 March 2007. AbstractIn this paper, silver plating graphite powders were developed by electroless plating method. The density of silver plating graphite powders was 2.61g/cm3 and the ratio of silver for the powders was 25wt%. After being mixed with epoxy resin and curing agent, silver pl

20、ating graphite powders conductive adhesive was obtained, with the percolation concentration of 28vol%. Compared to pure Ag conductive adhesive, the new conductive adhesive has the advantage of low cost. Adhesives based on the graphite or Ag plating graphite powders exhibited higher tensile strength

21、and larger failure elongations than pure Ag conductive adhesive.Keywords: Silver plating; Graphite powders; Conductive adhesiveArticle Outline1. Introduction 2. Experimental 2.1. Sliver plating 2.2. Conductive adhesives3. Results and discussion 4. Summary References1. IntroductionElectrically conduc

22、tive adhesives offer a new prospective way to electrical connection of surface mount device components to printed circuit boards, because of their lower possible curing temperature, higher flexibility, fine pitch capability than thin-lead solders 1, 2 and 3. Normally, high-performance conductive adh

23、esives were designed by combining the thermosetting resin and the efficient electrically conductive fillers. Silver is used as the most popular electrically conductive filler due to its superior conductivity. The silver filler has one disadvantage of higher cost than that of copper and carbon black.

24、 Graphite or carbon powders can be used as conductive fillers, but the conductivity of this kind of adhesives is not satisfactory enough. Now, silver-coated flake copper, inorganic particles or polymer micro-spheres using as the filler for conductive adhesives have been studied 4, 5 and 6. Consideri

25、ng various electrically conductive fillers, silver-coated inorganic particles or polymer micro-spheres are superior to graphite particles regarding the electrical conductivity of the adhesives, since the electrical conductivity of silver is much higher than that of inorganic particles. In addition t

26、o the high electrical conductivity of silver, the application of silver-plated particles leads also to the adhesives with low weight and low cost.In this paper, silver plating graphite powders were developed and a conductive adhesive was obtained using this silver plating graphite powders as the fil

27、ler.2. Experimental2.1. Sliver platingFive gram natural graphite powders with the average size of 17m were used as raw materials. The graphite powders were degreased in oven at 600C for 20min, and then were sensitized in 20% SnCl2 solution for 5min. After being rinsed with distilled water, the powde

28、rs were activated in 2% AgNO3 solution for 5min.The treated graphite powders were immersed in the reducing agent solution of water, in which the polyglycol, ethanol and glucose (C6H12O6) were contained, and then stirred for 10min.AgNO3 (99.8%) and aqueous ammonia (2830%) were used for preparation of

29、 Ag solution. Transparent Ag solution was first prepared by dissolving the AgNO3 (3.3g) in the water (180ml) with addition of several drops of the aqueous ammonia, then NaOH (0.6g) was added to the solution, finally several drops of aqueous ammonia were added until the Ag(NH3)+ solution became trans

30、parent again.The mixture of graphite powders and reducing agent solution were immersed in the Ag solution and stirred for 30min at room temperature, the pH is about 11 during coating process. After washing and drying, the silver plating graphite powders were obtained.The surface morphology of the Ag

31、 plating graphite powders were observed by using a scanning electron microscope (Hitch S-3000N), and the structure was analyzed by XRD (D/MAX-III).2.2. Conductive adhesivesIn this study, three kinds of conductive adhesives were developed with different fillers in a similar average size, pure Ag particles, graphite powders and Ag plating graphite fillers. The conductive adhesives comprised of fillers, epoxy resin and hardeners. The epoxy resin used was a diglycidyl ether of bisphenol-A, E51, from the Chenguang Research Institute of Che