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Ti-Ni-Fe 合金是一种形状记忆合金。一般认为这类合金的无公度相(Ⅰ相)和公度相(R相)是电荷密度波(CDW)调制结构。我们首次运用能同时测量电阻的超声测量技术,合理解释了 Ti_(50)Ni_(47.5)Fe_(2.5)多晶合金冷却过程中出现的两次声速极小和两个衰减峰,超声频率为13.9MHz。第一次冷却和升温及第二次冷却过程的超声衰减和声速变化的实验结果示于图1。X 射线衍射、差
Ti-Ni-Fe alloy is a shape memory alloy. It is generally accepted that the unacceptable phase (phase I) and the common phase (phase R) of these alloys are charge density wave (CDW) modulated structures. For the first time, we used the ultrasonic measurement technology that can measure the electrical resistance at the same time to reasonably explain the two minimum velocity of sound velocity and two attenuation peaks during the cooling process of the Ti_ (50) Ni_ (47.5) Fe_ (2.5) polycrystalline alloy. The ultrasonic frequency is 13.9 MHz. The experimental results of the ultrasonic attenuation and the sound velocity change of the first cooling and warming and the second cooling are shown in FIG. 1. X-ray diffraction, poor