【摘要】 本研究采用X射线衍射仪、透射电镜分析机械合金化过程中Cu_95-xCr₅Zr_x（x∈{1,3,5,7,8,9,10,12,15}）粉体的物相结构演变及微观组织的变化.通过对粉体热压成型后进行拉伸试验、导电率测试、金相组织和断口形貌观察.研究不同Zr含量对Cu_95-xCr₅Zr_x合金材料显微组织和性能的影响.结果表明:经过20～30 h机械合金化处理,Cu_95-xCr₅Zr_x合金粉体的XRD衍射峰发生展宽,TEM电子选区衍射中多晶环特征削弱,Cr、Zr以固溶体形式存在于Cu基体中.Cu_95-xCr₅Zr_x合金材料导电率随着Zr质量分数的增加由55.3%IACS逐渐降低至25.1%IACS,合金试样抗拉强度呈先増后减的趋势,抗拉强度值在Zr的质量分数为8%时达到最大830.1MPa.合金材料失效方式由脆性断裂逐渐转为韧性断裂.更多还原

【Abstract】 In this study, the phase evolution and microstructure of Cu_95-xCr₅Zr_x（x∈{1,3,5,7,8,9,10,12,15}）powder during mechanical alloying were characterized by X-ray Diffraction and Transmission Electron Microscopy. The tensile test, conductivity test, microstructure and fracture morphology of the alloy prepared by hot-pressed were observed. The effects of different Zr contents on the microstructure and properties of Cu_95-xCr₅Zr_x alloy were investigated. The results showed that the XRD diffraction peak of Cu_95-xCr₅Zr_x alloy powder is broadened after 20～30 h of mechanical alloying. The characteristics of polycrystalline ring in TEM electron-selective region diffraction are weakened. Cr and Zr are retained in the form of solid solution in the Cu matrix. With the addition of Zr, the conductivity of Cu_95-xCr₅Zr_x alloy gradually decreases from 55.3% IACS to 25.1% IACS. The tensile strength of the alloy sample is increases firstly and then decreases with the increase of temperature. When the addition amount of Zr is 8%（mass fraction）, the tensile strength of alloy material reaches the maximum value of 830.1 MPa. The brittle fracture gradually changes into ductile fracture.更多还原