中文摘要：

采用电弧炉制备了添加不同Gd含量的Ti—Ni—Gd三元合金，利用DSC、X射线衍射仪研究了重稀土元素Gd对Ti-50.7Ni合金的马氏体相变的影响。结果表明添加重稀土元素Gd后，Gd含量不超过2％（原子分数）时，淬火态的Ti—Ni—Gd三元合金中分别发生两步马氏体相变，Gd含量为10％（原子分数）时，合金中发生了一步马氏体相变，同时稀土元素Gd的加入能明显提高Ti—Ni合金的相变温度。Ti—Ni—Gd舍金中马氏体仍为B19’单斜结构，而且马氏体的点阵参数随Gd的加入发生明显变化，晶胞产生畸变。

英文摘要：

Martensitic transformation of （Ti49.3 Ni50. 7 ）1-x Gdx （x = 0, lat %, 2at %, 10at % ） shape memory alloys are investigated by X-ray diffraction （XRD） and differential scanning calorimetry （DSC）. The results show that the martensitic transformation type differs with different content of Gd adding to Ti-Ni alloys. In the alloy containing 2at% Gd, a two-step martensitic transformation is observed, whereas a one-step martensitic transformation is observed in the alloy containing 10at% Gd. The martensitic transformation temperatures increase rapidly with increasing Gd content to 2at%, and then tend to be stable when the Gd content is further increased, B19＇ martensite is observed in Ti-Ni-Gd alloys and its lattice is distorted with Gd addition.