【作者】 张家涛；

【导师】 段希祥； 孙加林；

【作者基本信息】 昆明理工大学 ， 矿物加工工程， 2001， 博士

【摘要】 论文提出一种新型高导电高强度Cu-Cr（Zr、Mg）自生复合材料，利用该材料，可在不改变传统生产工艺条件下连续生产出大截面、复杂形状的产品。该材料利用析出强化和层片状原位复合增强相来提高纵向强度，同时对导电性能影响很小，能以较低的成本满足强度及导电性要求。论文对自生复合材料的制备、成形过程进行了详细介绍和分析。通过扫描电镜和透射电镜对铸态、加工态、时效态等各种状态的微观组织结构进行系统观察；对第二相尤其是原位复合增强相的形貌特征、形成机理做了大量分析讨论。经过不同温度、不同时间的时效处理后，对自生复合材料的时效特性进行了探讨，总结出Cr颗粒在时效过程中的具体析出行为。通过再结晶对不同加工状态下自生复合材料的性能分析，归纳出冷变形、再结晶过程及时效析出的交互作用规律。同时，通过加入诸如Zr、Mg等添加元素，可以成功地避免限制传统Cu-Cr材料使用的热裂及高温软化等弊端，并讨论了这些元素对材料强度和导电性能的影响机制。为了获得不同强化机制、强化效果的最佳匹配，建立了数学模型来量化各机制对强度的贡献程度。在上述研究工作基础上，优化出最佳制备、热处理、成形工艺，并对具体生产实例进行指导。更多还原

【Abstract】 A new generation of Cu-Cr(Zr,Mg) in-situ composite, which possesses high strength and good electrical conductivity, is proposed in this thesis. By traditional ways, the material can be made into various-shaped products with large cross-section. It takes advantage of precipitation strengthening and ribbon-shaped in-situ composite phases to increase the longitudinal strength with little influences on conductivity, which fulfilled the requirements of both strength and conductivity at lower cost. In the thesis, the preparation and forming processes of in situ composite are introduced and analyzed in detail. By means of SEM and TEM technique, the microstructures in the states of casting, cold working and aging are observed and the second phases, especially the in-situ strengthening phases are analyzed. After aging of various time and temperatures, the aging characteristics is discussed and the precipitating action of Cr particles is described and the relationship among the recrystallization, cold working and chromium precipitation are concluded. At the same time, by adding metal elements such as Zr and Mg. it succeeds in avoiding the tendencies of thermal crackle and high-temperature softening, which confined the usage of traditional Cu-Cr alloys. The mechanism of these elements to the strength and conductivity are also discussed. To get the best results of different strengthening mechanism, mathematical model are built to quantify them. At last, the optimum technology processes including preparation, heat treatment and forming is put forward and the application example, which is guided by the technology processes, has been completed.更多还原