【摘要】 研究了稀土元素钕(Nd)对Ti50Ni48Fe2形状记忆合金相变行为和微观结构的影响。采用电阻测试,光学显微镜,电子探针分析仪以及X射线衍射等方法对合金进行表征。结果表明不同Nd含量的Ti50Ni48-xFe2Ndx合金的相变行为均呈现两步马氏体相变,Nd含量为0.1at.%时,马氏体相变温度(MS)从212K急剧升高到267K,随着Nd元素的进一步添加,MS开始逐渐降低。TiNiFeNd四元合金的微观组织由TiNi基体相,Ti2Ni第二相和Nd3Ni金属间化合物组成,其中Nd3Ni析出颗粒以球状形态均匀分布于基体中。更多还原

【Abstract】 The influences of rare earth element Nd on the phase transformation and the microstructure of Ti50Ni48?xFe2Ndx shape memory alloys are investigated by means of electrical resistivity, optical microscopy, electron probe microanalyzer, and X-ray diffraction. The results show that TiNiFe alloys with different Nd contents exhibit two-step martensitic transformation. The start temperature of martensitic transformation increases sharply from 212 K to 267 K when 0.1 at.% Nd is added in, and then decreases gradually if Nd content further increases. The microstructure of TiNiFeNd quaternary alloys consists of TiNi matrix, Ti2Ni second phase, and Nd3Ni intermetallic compound. The spherical Nd3Ni precipitate-particles evenly disperse in the matrix.更多还原