Martensitic transformation in Ni–Fe–Ga alloys
Martensitic transformation in Ni–Fe–Ga alloys
复制标题
DOI：
10.1016/j.msea.2007.05.097
复制
发表时间：
2008-04
期刊：
影响因子：
6.4
通讯作者：
J. Barandiaran;J. Gutiérrez;P. Lázpita;V. Chernenko;C. Seguí;J. Pons;E. Cesari;K. Oikawa;T. Kanomata
中科院分区：
文献类型：
--
作者：
J. Barandiaran;J. Gutiérrez;P. Lázpita;V. Chernenko;C. Seguí;J. Pons;E. Cesari;K. Oikawa;T. Kanomata
铁基铁磁形状记忆合金由于其良好的延展性，与传统的Ni_2MnGa合金相比，具有优异的力学性能。这为磁传感器或执行器等技术应用开辟了新的可能性。在这项工作中，我们提出了一个多技术研究的名义成分Ni 55-xFe 19 + xGa 26（x=0，1和2）转变接近室温的合金马氏体相变。用SQUID磁强计和交流方法进行的磁性表征表明，居里温度（TC ~ 300 K）随Fe含量的增加而增加，而马氏体温度（TM ~ 240 K）随Fe含量的增加而降低，与DSC和电阻率测量结果一致。此外，通过磁性测量发现了几个居里温度，表明合金中不同相共存。中子衍射研究表明奥氏体为L21有序立方相，马氏体为14 M结构。从衍射峰的温度演化中观察到这种转变。
Fe-based ferromagnetic shape memory alloys have attractive mechanical properties as compared with the classical Ni2MnGa ones, because of their enhanced ductility. This opens new possibilities regarding technical applications as magnetic sensors or actuators. In this work, we present a multiple technique study of the martensitic transformation in alloys with nominal composition Ni55−xFe19+xGa26(x=0, 1, and 2) transforming close to room temperature. Magnetic characterisations, performed in a SQUID magnetometer and by AC methods show the Curie temperature (TC≈300K) increasing with Fe content while the martensitic temperature (TM≈240K) decreases, in agreement with DSC and resistivity measurements. In addition, several Curie temperatures are found by the magnetic measurements, indicating the coexistence of different phases in the alloy. Neutron diffraction study suggests the L21-ordered cubic phase for austenite and 14M structure for the martensitic phase. The transformation is observed from the temperature evolution of the diffraction peaks.