Synthesis Of Agcuo Composites Even And Interface Structure Research

Silver metal oxides are composites of particle reinforced metal matrix.The dispersion degree of secondly phase metal oxides, which can be shown homogeneous degree of microstructures for the composites, can effect using properties of particle reinforced metal matrix composites. Meanwhile, the relationship of interface for matrix and secondly phase particles can also influence or decide improving for integrative properties of particle reinforced metal matrix composites. It has been known that the technique of in-situ reaction synthesis fabrication can resolve the interface problem of particle reinforced metal matrix composites. But the microstructure of the composites fabricated by the reaction synthesis technique is heterogeneous, which has the character of celluar and circularly distributing of the second phase in the circumference of the matrix. This heterogeneous microstructure brings that it is difficulty to process even more fracture owing to secondly particle jam with process program, which the yield is lower and industrialized application for particle reinforced metal matrix composites fabricated by in-situ reaction synthesis is restricted. The effective technique of fabrication and process will be found to improve microstructure homogeneity, which can accelerate industrialized application of particle reinforced metal matrix composite fabricated by in-situ reaction synthesis. Therefore, it has important significance to investigation the technique and method about microstructure homogeneity of silver metal oxide composites for being propitious to improve its properties and industrialized application, in which, there is also referential use for others particle reinforced metal matrix composites fabricated by in-situ reaction synthesis.In this paper, silver copper oxide composite adopting in-situ reaction synthesis fabrication was investigated. Firstly, reaction thermodynamics of silver copper oxide and reactive grown kinetics of copper oxide were analyzed. Then, the microstructures of in-situ reaction fabrication silver copper oxide were investigated by the instrument of analysis and test such as XRD, SEM, HRTEM, et al. Secondly, the effect of severe plastic deformation on microstructure and properties of silver copper oxide composites was studied. Meanwhile, the necessary condition of microstructure homogeneity after severe plastic deformation was also gained in this paper. Thirdly, the stability of the interface in silver copper oxide was simulated, calculated and analyzed by the first-principles. The microstructure of silver copper oxide was homogeneity by severe plastic deformation. Important results are as follows:According to analysis of thermodynamics such as oxygen partial press, the fabrication process of in-situ reaction synthesis that can successfully fabricate silver copper oxide composites were obtained.The results of investigating grown kinetics for copper oxide reaction showed that reaction and grown of copper oxide were dependent on diffusion ability of copper and oxygen in silver and partial pressure of oxygen around silver copper particles. The results also show that reactive synthesis of silver copper in reactive synthesis silver copper oxide composites was controlled by diffusion rate of copper in silver:the reaction and grown of copper oxide were controlled by diffusion rate of copper on silver matrix interface and oxygen partial pressure around silver copper particles at lower temperature, and the reaction and grown of copper oxide were controlled by diffusion rate of copper in silver matrix and oxygen partial pressure around silver copper particles at higher temperature. Therefore, microstructure of reactive synthesis silver copper oxide was distributed circularly around silver matrix particles.The results for effect of severe plastic deformation on microstructure evolvement disciplinarian and properties of silver copper oxide composites fabricated by reactive synthesis showed that the microstructure of silver copper oxide composites can be homogeneity by severe plastic deformation technique, and the necessary conditions of microstructure homogeneity by severe plastic deformation are that the secondly particles have been fine after reactive synthesis and the stain of severe plastic deformation is bigger. Meanwhile, the properties of silver copper oxide composites can be also improved with increase of the strain.There are two types of copper oxide with cubic and monoclinic crystal structures in silver copper oxide composites fabricated by reactive synthesis. The plastic deformation behavior of copper oxide with cubic crystal structure was firstly found at investigating the microstructure evolvement disciplinarian of silver copper oxide composites by severe plastic deformation. The plastic behavior is the inter character of cubic copper oxide.The results of the first-principles calculation and simulation by density functional theory, and the experiments showed that the interface of Ag (110)/CuO (100)-Monoclinic is best stable in Ag/CuO(Monoclinic) interfaces and the interface of Ag (110)/CuO (110)-Cubic was best stable in Ag/CuO(Cubic) interfaces. The calculated results for the bond populations and spatial distribution of the charge density of Ag/CuO (Monoclinic) interface suggested that the best stable interface is the interface in which matrix silver bond with oxygen and copper in copper oxide, the second stable interface was the interface in which matrix silver bond copper through oxygen, and unstable interface is a physical adsorption interface between matrix silver and copper oxide.