导　　师： 江学良

学科专业： 070305

授予学位： 硕士

作　　者： ;

机构地区： 武汉工程大学

摘　　要： 在电流的输送和电信号的转换进程当中,电接触材料发挥着关键的功能。它是生产各种电路控制器/(如保护开关、接触器、断路器、汽车电子电器仪表等/)的重要材料,承担着电路接通和负载电流的任务。电接触材料性能的优劣对电器开关的接触可靠性有重要的影响。目前由于电器产品种类日益繁多，为满足电器能较好的应用在不同的场合，各类电器产品对电接触材料的性能（如导电导热性、抗氧化性、抗熔焊性以及耐电弧侵蚀性）会有不同的要求，从而促进电接触材料的种类和制备技术不断改进和发展。本论文采用化学镀的方法合成Ag基电接触材料，探究了敏化剂氯化亚锡、硝酸银的浓度、反应时间、反应温度等工艺条件对复合粉末的形貌晶型和材料物理性能的作用。主要研究内容和结果如下： 1.采用氯化亚锡为敏化剂，以甲醛为还原剂，在石墨粉表面化学镀银，合成Ag//C电接触材料。用X射线衍射、扫描电镜表征了复合粒子的形貌和晶型，研究了敏化剂氯化亚锡、硝酸银浓度、反应时间、反应温度对合成Ag//C电接触材料形貌和晶型的影响，以及不同还原剂对合成复合粒子质量的影响。结果表明：采用甲醛为还原剂，经过敏化处理后，当硝酸银浓度为0.4mol//L时，在温度为65℃下，合成的Ag//C电接触材料有较好的形貌。研究了不同还原剂甲醛、水合肼、葡萄糖对Ag//C复合粉末物理性能的影响。通过测试复合粉末的维氏硬度、抗压强度、密度以及电阻率。结果表明，还原剂为甲醛时，合成的Ag//C复合粉末有较好的物理性能。 2.因为铜-银复合粉末拥有较好的抗熔焊性、耐电弧侵蚀性能、高的导电导热性，它在电器产品、功能相填料等众多范畴具有广泛的使用价值。利用化学镀的方法，采用氯化亚锡为敏化剂，甲醛为还原剂，合成了用于电子浆料的铜-银复合粉末。用X射线衍射、扫描电镜表征了复合粒子的晶型和形貌结构，研究了敏化剂氯化亚锡、反应温度，还原剂以及镀液的pH值对材料晶型和形貌的影响。结果表明：采用甲醛为还原剂，经过敏化处理后，当溶液的pH值为10时，在50℃下，合成的银包铜粉电接触材料有较好的形貌。研究了不同还原剂甲醛、水合肼、葡萄糖对Ag//Cu复合粉末物理性能的影响。通过测试复合粉末的维氏硬度、抗压强度、密度以及电阻率。结果表明，还原剂为甲醛时，合成的Ag//Cu复合粉末有较好的物理性能。 3.采用化学镀的方法，在铝粉的表面包覆一层银颗粒，合成了物理性能优异的Ag//Al电接触材料。并且利用X射线衍射、扫描电镜表征了复合粒子的形貌和晶型，研究了敏化剂氯化亚锡、硝酸银浓度、反应时间、反应温度对合成Ag//Al电接触材料形貌和晶型的影响，结果表明：采用甲醛为还原剂，经过敏化处理后，当硝酸银浓度为0.4mol//L时，在温度为65℃下，反应60min，合成的Ag//Al电接触材料有较好的形貌。研究了不同还原剂甲醛、水合肼、葡萄糖对Ag//Al复合粉末物理性能的影响。通过测试复合粉末的维氏硬度、抗压强度、密度以及电阻率。结果表明，还原剂为甲醛时，合成的Ag//Al复合粉末有较好的物理性能。 Electric contact materials played important roles in the process of transporting electriccurrent and converting electrical signal. They were important materials in circuit controller/(e.g., protection switch, contactor, circuit breaker, automobile electronic instruments, etc,/)they undertook the task of connecting circuit and loading current. The property of electriccontact materials played important roles on performance of the electric switch.At presentelectrical products had different requirements of electrical contact materials /(such asheat-conducting property, oxidation resistance, resistance to fusion welding and arcerosion./) as electrical products increased widely,contributing to the type and preparationtechnology improving and developing. In this research, Ag-based electrical contactmaterials were synthesized by chemical plating. The sensitizer, silver nitrate concentration,reaction time， reaction temperature were studied on the effects of Ag-based electricalcontact material morphology and polymorphs. The contents and results mainly as follow: 1. Ag//C electrical contact material were synthesized by chemical plating method，using stannous chloride as a sensitizer, formaldehyde as a reducing agent. Themorphology and polymorphs of the composite particles were characterized by X-raydiffraction, scanning electron microscopy. The effects of the sensitizer， silver nitrateconcentration, reaction time，reaction temperature on the surface and crystal morphologiesof Ag//C electrical contact material were investigated. And the effects of different reducingagents on quality of composite particles were studied. The results show that usingformaldehyde as a reducing agent， after sensitization, when the silver nitrateconcentration was0.4mol//L, reaction temperature was65°C，the synthesis of Ag//Celectrical contact material had good morphology. The effects of different reducing agent onphysical properties of Ag//C composite powders were investigated. Physical properties ofcomposite powders were studied by testing their vicker-hardness, compressive strength,density and resistivity. The results showed that Ag//C composite powder had good physical properties when reducing agent was formaldehyde. 2. As silver-copper composite powders had good resistance to fusion welding，goodresistance to arc erosion and high heat-conducting property, they were widely used inelectric products, function packing and other fields.Silver-copper composite powders weresynthesized by chemical plating method in which the stannous chloride and formaldehydewere used as sensitizer and reducing agent, respectively. The morphology and polymorphsof the composite particles were characterized by X-ray diffraction, scanning electronmicroscopy. The effects of sensitizer stannous chloride, reaction temperature, reducingagent and pH value of solution on the surface and crystal morphologies of the compositeparticles were investigated. Results show that using formaldehyde as a reducing agentwith the post-treatment of sensitization, the silver-plated copper powders with wellmorphology can be obtained when the pH value of solution is10and the reactiontemperature is kept around50℃. The effects of different reducing agent on physicalproperties of Ag//Cu composite powders were investigated. Physical properties ofcomposite powders were studied by testing their vicker-hardness, compressive strength,density and resistivity. The results showed that Ag//Cu composite powder had goodphysical properties when reducing agent was formaldehyde. 3. Ag//Al electrical contact materials which have excellent physical properties weresynthesized by chemical plating method by plating silver particles on the surface ofaluminum powder.The morphology and polymorphs of the composite particles werecharacterized by X-ray diffraction, scanning electron microscopy. The effects of sensitizerstannous chloride, silver nitrate concentration, reaction time, reaction temperature werestudied on the effects of Ag//Al electrical contact material morphology and polymorphs.Results show that using formaldehyde as a reducing agent with the post-treatment ofsensitization, the silver-plated aluminum powders with well morphology can be obtainedwhen the reaction time is60min and the reaction temperature is kept around45℃. Theeffects of different reducing agent on physical properties of Ag//Al composite powderswere investigated. Physical properties of composite powders were studied by testing their vicker-hardness, compressive strength, density and resistivity. The results showed thatAg//Al composite powder had good physical properties when reducing agent wasformaldehyde.

关 键 词： 石墨粉 银 铜复合粉 敏化 化学镀银 电接触材料

分 类 号： [TQ150]

领　　域： [化学工程]