中文摘要：

利用Rietveld方法对三元体系Ce-Al-Cu（〈50%（原子分数）Cu）中的化合物晶体结构进行修正,验证该体系在传统高频电弧熔炼条件下所得的熔铸合金存在16个单相。利用精修得到的晶体结构参数对其熔铸态固溶度范围进行了计算,发现Cu在Al,α-Ce3Al11,CeAl3和CeAl2中的最大固溶度依次是（原子分数）2.48%,1.6%,3.7%和5.3%,Al在CeCu5中的最大固溶度为44.1%,Al2Cu和AlCu的固溶度区域分别为（原子分数）32.1%~32.7%Cu和53.5%~57.3%Cu。证实在熔铸态下研究的体系中存在5个三元化合物：CeAl12-xCux（4.0≤x≤4.53）,CeAl4-xCux（0.73≤x≤1.10）,Ce2Al17-xCux（6.49≤x≤7.87）,CeAl13-xCux（6.62≤x≤6.92）和Ce2AlCu2,而Al92Ce8,Al3Cu2和CeAlCu并不存在。

英文摘要：

By use of the Rietveld method for the refinement of the crystal structure of compounds in the system Ce-Al-Cu（50%Cu） in as-cast state formed by conventional arc-melting,the existence of 16 single phases was determined.Derived from the Rietveld refinement results of the cell dimensions.The maximum solid solubility of these compounds was determined.In as-cast state,the maximum solid solubilities of Cu in Al,α-Ce3Al11,CeAl3 and CeAl2 were about 2.48%,1.6%,3.7% and 5.3%,respectively,and Al in CeCu5 was about 44.1%.The homogeneity ranges of Al2Cu and AlCu phases extended from about 32.1% to 32.7% Cu and 53.5% to 57.3% Cu,respectively.The five ternary compounds and their solid solutions were observed in the following compounds： CeAl12-xCux（4.0≤x≤4.53）,CeAl4-xCux（0.73≤x≤1.10）,Ce2Al17-xCux（6.49≤x≤7.87）,CeAl13-xCux（6.62≤x≤6.92） and Ce2AlCu2.However,the compounds Al92Ce8,Al3Cu2 and CeAlCu reported in former literatures were not obtained in their as-cast samples.And they were decomposed into other phases after arc-melted.