Morphology evolution and crystallographic feature of Nb nanowire in an in-situ NiTi-Nb nanocomposite

作者：Liu Zhen Yang; Guo Fang Min; Wang Zhong Qiang; Cui Li Shan^*

来源：Rare Metals, 2014, 33(5): 563-567.

DOI：10.1007/s12598-014-0341-0

• Deep drawing
• Nanowire
• Metal matrix composite
• TEM

In-situ NiTi shape memory alloy-Nb nanowire nanocomposite was revealed to exhibit exceptional mechanical properties. The properties of high strength and ultra-large elastic strains are closely related with the high performance of in situ-formed Nb nanowire reinforcements. In this study, the morphology evolution and crystallographic feature of Nb nanowires in NiTi shape memory alloy matrix during cold drawing were investigated by means of transmission electron microscopy (TEM). It is revealed that, as a result of the severe work hardening and amorphization of NiTi matrix, the cold work reduction of nanowire reinforcements can exceed that of the entire composite. The irregular-shaped Nb nanowires are reshaped to straight and smooth nanowires during cold drawing process. By means of TEM nanobeam diffraction, it is revealed that the in situ-formed Nb nanowire in such top-down processed NiTi-Nb composite keeps single crystalline over 1,000 nm at length direction. As a consequence, the aspect ratio of nanowire reinforcements in NiTi matrix exceeds 25:1.

• 出版日期2014-10
• 单位中国石油大学（北京）