Co41Ni33-xAl26Cux的马氏体相变和磁性转变

Martensitic Transformation and Magnetic Transition of Co41 Ni33-x Al26 Cux Alloy

Co-Ni-Al合金具有良好的加工性能，是很有前途的铁磁性形状记忆合金，本文通过金相显微分析、DSC、VSM方法，研究了Cu含量X对Co41Ni33-xA126Cu。合金马氏体相变和Curie点影响。结果发现在x≤5％范围内，C04lNim33-xAl26Cux合金马氏体相变温度与x的关系成直线变化，马氏体相变温度随x增加而迅速降低，x每增加1％，马氏体相变温度降低约44K；其Curie点随x增加而缓慢下降，x每增加1％，Curie点约降低3．6K。与L10马氏体结构的Co4lNi33-xA126Cux（x=0，3，5）合金相比，具有B2结构的Co41Ni25A126Cu8合金易磁化，并且饱和磁化强度低。

Co - Ni - Al alloy is a promising ferromagnetic shape memory alloy for its good workability. The influence of Cu concentration x on the martensitic transformation temperature and Curie point of Co41 Ni33-x.Al26Cux alloys were investigated by optical metallography, SEM, DSC and VSM methods in this study. It was found that the martensitic transformation temperatures of Co41Ni33-xAl26 Cux alloys decrease quickly with the increasing of Cu concentration x. In the range of x≤5%, 1% Cu substitute Ni can decrease the martensitic transition temperature by 44K for alloys quenched from 1623K. Whereas the influence of x on Curie point isn＇t so strong, the decreasing in Curie point is only 3.6K for 1% increasing of Cu element. Comparing to Co41 Ni33 - xAl26Cux （ x = 0, 3, 5 ） alloys with L10 martensitic crystal structure, Co41 Ni25Al26Cu8 with B2 crystal structure is easy to be magnetized and has the lowest magnetization saturation.