High-temperature shape memory properties of Cu15Ni35Ti25Hf12.5Zr12.5 high-entropy alloy

Journal of Materials Research and Technology

Ming-Yen Lu¹  Che-Wei Tsai²  Shan-Hsiu Chang²  Kai-Yuan Hsiao²  Jien-Wei Yeh²  Wei-Pin Kao² 

[1] High Entropy Materials Center, National Tsing Hua University, Hsinchu 30013, Taiwan, ROC;Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan, ROC;

关键词: High-entropy alloy;    Shape memory alloy;    High-temperature martensitic transformation;    Dilatometer;    Shape recovery ratio;   

DOI  :  

来源: DOAJ

【 摘 要 】

The major challenges hindering the application of high-temperature shape memory alloys are their decreased mechanical strength and thermal stability. Herein, we present high-temperature shape memory properties of the Cu15Ni35Ti25Hf12.5Zr12.5 high-entropy alloy with improved mechanical properties and superior shape memory characteristics. Under an immense stress of 1400 MPa, the alloy exhibited a shape recovery ratio of 88.7%. Using an in-situ high-temperature X-ray diffractometer, the alloy was established to undergo phase transformation from B19′ to B2 phase. Additionally, the alloy exhibited a martensitic transformation temperature higher than 100 °C. The fracture strength and ductility were 1670 MPa and 24.7%, respectively, as measured by compression tests. The deformation mechanism and shape recovery phenomenon of this shape memory alloy are also discussed. This study demonstrates the potential of high-entropy shape memory alloys for high-temperature applications.

【 授权许可】

Unknown