Microstructure, microhardness and phase transformation characteristics of Ni50+xFe25-xGa25 shape memory alloys

作者：Li Y^*; Chen J; Jiang CB; Xu HB

来源：Rare Metal Materials and Engineering, 2004, 33(6): 199-202.

• NiFeGa
• shape memory alloy
• microstructure
• micro-hardness
• martensitic transformation

The microstructure, microhardness and martensitic transformation characteristics of the Ni50+xFe25-xGa25 (x=5,6,7, 8 at%) shape memory alloys were investigated by x-ray diffraction, Vickers hardness and DSC measurements respectively. Binary phase morphologies, the martensitic and the gamma phases were observed in the as-melted alloys at room temperature. The martensitic phase has a simple non-modulated or a complex modulated structure dependent on the composition and annealing, while the gamma phase was confirmed as a FCC structure with a relatively stable lattice parameter. The results also show that the Vickers hardness of the two phases increases with the increase of Ni content. The effects of annealing at 1 423 K for 5 h on the microstructures, micro-hardness and phase transformation temperatures of the alloys were also studied.

• 出版日期2004-6
• 单位北京大学