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用熔剂法制备了（Ｎｂ＿ｙ．Ｔｉ＿（１－ｙ））Ｃ＿ｒ单晶体，用Ｄｅｂｙｅ照相法及四圆衍射仪对其晶体结构进行了研究。实验结果表明，（Ｎｂ＿ｙＴｉ￣（１－ｙ）Ｃ＿ｘ中存在类似于作化学计量化合物ＴｉＣ＿ｘ及ＮｂＣ＿ｘ的有序一无序转变现象，转变温度随其化学成份改变在１１７５～１２８０Ｋ范围内变化。高温型（Ｎｂ＿ｙＴｉ￣（１－ｙ））Ｃ＿ｘ的晶体结构属ＮａＣｌ型结构，碳空位呈随机分布；低温型（Ｎｂ＿ｙＴｉ￣（１－ｙ））Ｃ＿ｘ的晶体中碳空位呈短程有序分布，可用Ｖ＿６Ｃ＿５晶体结构模型进行描述。
The crystal structure of (Nb_y.Ti_ (1-y)) C_r was prepared by flux method and its crystal structure was studied by Debye method and four-circle diffractometer. The experimental results show that there exists an ordered and unordered transition similar to that of the stoichiometric compounds TiC_x and NbC_x in (Nb_yTi¯- (1-y) C_x), the transition temperature changes with the change of its chemical composition in the range of 1175 ~ 1280 K. The high temperature type (Nb_yTi¯- (1-y)) C_x belongs to the NaCl type structure and the carbon vacancies are randomly distributed. The carbon vacancy in the low-temperature type (Nb_yTi¯- (1-y)) C_x exhibits a short-range orderly distribution and the available V_6C_5 crystal Structural model is described.