开孔泡沫金属的功能化应用基础研究

发布时间：2018-03-30 17:01

本文选题：泡沫金属　切入点：摩擦学材料　出处：《南京航空航天大学》2016年博士论文

【摘要】：以轻质结构材料的功能化应用需求为背景,结合现代交通、通讯、能源、电力的技术特点,充分运用生物千万年演化所形成的优质结构和材料组合,以生物结构与材料宏微观几何结构与材料拓扑规律为模板,研究以电沉积为特征的轻质开孔泡沫金属制造技术。建立以多孔泡沫金属制备为代表的仿生制造体系,优化了不同孔密度和孔隙率的泡沫金属相关制备技术和经济环保的工艺,实现了可依据泡沫金属使用领域的反馈式设计制备体系,为泡沫金属的功能化应用提供了良好的材料设计和制备基础。同时,结合泡沫金属轻质多孔、比表面积大、孔隙率高且具有母体金属的理化特性,开展了泡沫金属的功能化应用基础研究,以加快泡沫金属的功能化产品发展进程。其功能化应用包括:泡沫金属增强的减磨耐磨材料设计、泡沫金属表面润湿性应用研究、泡沫铅电池板栅材料的电化学性能研究、泡沫金属及其与碳系纳米材料复合的电磁屏蔽性能研究、泡沫金属在气体/流体中的热学特性研究五个方面。考察了泡沫金属在每种功能化应用中的最佳结构参数,例如泡沫金属的孔密度、孔隙率等参数,其中取得的相关结论简介如下:(1)泡沫金属增强的减磨耐磨材料设计方面,向泡沫金属骨架中填充多种润滑材料制备了一系列泡沫金属增强的减磨耐磨材料,有效提高了基体聚合物的耐磨性能;(2)泡沫金属表面润湿性应用研究方面,通过对泡沫金属骨架表面润湿性能的改性,研制了仿水黾的超疏水泡沫金属浮体材料、油水分离材料,以及作为雾气收集器时润湿性与离心辅助收集效率的关系;(3)泡沫铅电池板栅材料的电化学性能研究方面,在泡沫铜基底上电沉积一层致密的铅层制备了泡沫铅用作铅酸蓄电池的集流体板栅,泡沫铅具有比传统铸造铅板栅更大的比表面积,可有效提高铅酸电池活性物质利用率和比能量;(4)泡沫金属及其与碳系纳米材料复合的电磁屏蔽性能研究方面,测试了泡沫铜、泡沫镍、泡沫铜镍合金以及与碳纳米管、石墨烯复合后在X波段的电磁屏蔽屏蔽性能,泡沫金属三维连通的结构使得电磁波入射到材料表面及内部时产生多次反射和散射损耗,直至被吸收,辅以碳系纳米层的吸收散热效应,使得该类复合材料具有较高的电磁屏蔽效能;(5)泡沫金属在气体/流体中的热学特性研究方面,将泡沫铜用作外置的散热翅片和热管类吸液芯,建立了一套可视化泡沫金属表面池沸腾现象研究装置,考察了泡沫铜表面的气泡成核机理,为泡沫铜气固耦合和流固耦合散热模式的应用提供了设计基础。
[Abstract]:Based on the functional application requirements of lightweight structural materials and the technical characteristics of modern transportation, communication, energy and power, the high quality structure and material combination formed by the evolution of biology over thousands of years are fully utilized. The fabrication technology of light porous foam metal characterized by electrodeposition was studied based on the template of macrostructure, macrostructure and material topology of biological structure and material. A biomimetic manufacturing system, represented by the preparation of porous foam metal, was established. The relative preparation technology of foam metal with different pore density and porosity and the economical and environmental protection technology are optimized, and the feedback preparation system can be designed according to the application field of foam metal. It provides a good material design and preparation basis for the functional application of foamed metal. At the same time, it combines the light porous metal, large specific surface area, high porosity and physical and chemical properties of parent metal. The basic research on functional application of foam metal was carried out in order to accelerate the development process of functional products of foam metal. The functional applications included: the design of antiwear material reinforced by foam metal, the application of wettability on the surface of foam metal, Electrochemical properties of lead foam battery grid materials, electromagnetic shielding properties of foam metals and their composites with carbon nanocomposites, The thermal properties of foam metal in gas / fluid are studied in five aspects. The optimum structural parameters of foam metal in each functional application, such as pore density and porosity of foam metal, are investigated. The related conclusions are summarized as follows: (1) A series of foam metal reinforced antiwear and wear resistant materials were prepared by filling various lubricating materials into the foam metal skeleton in the design of antiwear and wear resistant materials reinforced by foam metal. The surface wettability of foam metal was improved effectively. By modifying the surface wettability of foam metal skeleton, the superhydrophobic foam metal floatation material, oil-water separation material, was developed. And the relationship between wettability and centrifugal auxiliary collection efficiency as a mist collector. A dense lead layer was electrodeposited on a copper foam substrate to prepare a fluid collecting grid for lead-acid batteries. The lead foam has a larger specific surface area than the conventional cast lead grid. It can effectively improve the utilization ratio of active substances and specific energy of lead acid battery) foam metal and its composite with carbon nanomaterials. The foam copper, foamed nickel, foamed copper-nickel alloy and carbon nanotubes were tested. The electromagnetic shielding performance of graphene composite in X band, the structure of three-dimensional connection of foam metal causes multiple reflection and scattering loss of electromagnetic wave when incident to the surface and inside of material, until it is absorbed. In addition to the absorption and heat dissipation effect of carbon nanolayers, this kind of composite has a high electromagnetic shielding effect. In the study of thermal properties of foam metal in gas / fluid, copper foam is used as heat dissipating fin and heat pipe absorbent core. In this paper, a set of visualization device for the study of pool boiling on the surface of metal foam is established, and the mechanism of bubble nucleation on the surface of copper foam is investigated, which provides the design basis for the application of gas-solid coupling and fluid-solid coupling heat dissipation mode of copper foam.
【学位授予单位】：南京航空航天大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TG14;TB383.4

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