Deformation mechanism of Ni54Mn25Ga20.9Gd0.1 high-temperature shape memory alloy

作者：Zhang, Xin^*; Sui, Jiehe; Cai, Wei; Liu, Qingsuo; Liu, Ailian

来源：Intermetallics, 2015, 67: 52-55.

DOI：10.1016/j.intermet.2015.07.017

• Shape-memory alloys
• Martensitic transformation
• Microstructure
• Electron microscopy, transmission
• Mechanical testing

Ni54Mn25Ga20.9Gd0.1 Polycrystalline high-temperature shape memory alloy displayed high compressive fracture strain of 24.6% and large shape memory effect of 7.5%. However, its deformation mechanism was still unknown. In this paper, the structure revolution characterized by XRD and TEM indicated a new deformation mechanism different before was found. The deformation process of Ni54Mn25Ga20.9Gd0.1 alloy could be divided into four stages, including elastic deformation of non-modulated tetragonal martensite (T), stress-induced T to seven-layered modulated martensite (7 M) transformation, variants reorientation of 7 M, and elastic plastic deformation of reoriented 7 M. The 7 M formed by compression deformation disappeared completely after heating to the temperature above A(f).

• 出版日期2015-12
• 单位天津理工大学; 哈尔滨工业大学; 黑龙江科技大学