|
In this thesis, microstructures and properties of a Cu-Cr-Zr alloy with high strength and high electrical conductivity are studied. The specimens of solid solution and after aging of the alloy have been systematically observed and analyzed by means of SEM, TEM, XRD and EDS, the morphological and structural aspects of precipitate and its formation mechanism were also studied in detail. The characters of the alloy at different aging stages are surveyed, and the relationship between precipitation and aging treatments of the Cu-Cr-Zr alloy is then summarized. Moreover, the mechanical property, the electrical conductivity and the wear property of the alloy at different states are also investigated, and the effect of the microstructure on the properties of the alloy is discussed in order to get the optimal treatment condition of Cu-Cr-Zr alloy. It is found that by addition of low-alloying elements, solid solution strengthening, aging strengthening and strain hardening, the strength of Cu alloy increases greatly while its electrical conductivity shows no significant drop. Therefore, it is concluded that above Cu-based Cu-Cr-Zr alloy is a promising conductive material with a high electrical conductivity and high strength as well.Furthermore, the microstructure and property of another Cu-based conductive material, Cu-Cr in-situ composite material, is studied in this thesis. At the same time, preliminary survey of fabrication and microstructure of in-situ Cu-nanoscaleTiB2 composite is also presented in the thesis.
|