纳米Fe-Cu体系的结构和电阻温度特性

采用机械合金化方法制备了亚稳Fe50Cu50纳米合金粉末,压片后在氩气中分别进行523 K、873 K热处理。利用X-ray衍射和M ssbauer效应对样品的结构和相变进行了分析,结果表明,机械合金化后的样品为面心立方结构的固溶体,经523K热处理后,亚稳合金已开始分解;经873 K热处理后,样品已完全转变为纳米尺寸的α-Fe和Cu的混合体。在15~295 K内对热处理后样品的电阻进行了测量,结果表明,样品表现为负的电阻温度系数。

Structure and resistance temperature property of nano-sized Fe-Cu system

Metastable nano-sized Fe_(50)Cu_(50) alloy powders were prepared by mechanical alloying mechanical alloying,followed by being pressed into pellets.The pellet specimens were heat-treated in argon atmosphere at 523 K and 873 K,respectively.The structure and phase transition were investigated using X-ray diffraction and Mssbauer effect.It was shown that the mechanically alloyed specimens were fcc solid solutions,and the metastable alloys decomposed at 523 K,and ultimately transformed into a mixture of nano-sized α-Fe and Cu at 873 K.The measurement results of resistance of the specimens show the negative resistance temperature coefficient in the temperature range from 15 K to 295 K.