Transformation Behavior and Shape Memory Effect of Ni<sub>47</sub>Ti<sub>44</sub>Nb<sub>9</sub> Alloy Synthesized by Laser Powder Bed Fusion and Heat Treating
Mingyan Sun,
Jie Chen,
Qichao Fan,
Chuan Yang,
Guowei Wang,
Xianfeng Shen,
Yangyang Wang,
Yonghao Zhang,
Shuke Huang
Affiliations
Mingyan Sun
Institute of Machinery Manufacturing Technology, China Academy of Engineering Physics, Mianyang 621900, China
Jie Chen
Institute of Machinery Manufacturing Technology, China Academy of Engineering Physics, Mianyang 621900, China
Qichao Fan
Institute of Machinery Manufacturing Technology, China Academy of Engineering Physics, Mianyang 621900, China
Chuan Yang
Institute of Machinery Manufacturing Technology, China Academy of Engineering Physics, Mianyang 621900, China
Guowei Wang
Institute of Machinery Manufacturing Technology, China Academy of Engineering Physics, Mianyang 621900, China
Xianfeng Shen
Institute of Machinery Manufacturing Technology, China Academy of Engineering Physics, Mianyang 621900, China
Yangyang Wang
Institute of Machinery Manufacturing Technology, China Academy of Engineering Physics, Mianyang 621900, China
Yonghao Zhang
Institute of Machinery Manufacturing Technology, China Academy of Engineering Physics, Mianyang 621900, China
Shuke Huang
Institute of Machinery Manufacturing Technology, China Academy of Engineering Physics, Mianyang 621900, China
Ni47Ti44Nb9 alloys were successfully fabricated by laser powder bed fusion (LPBF) technique with different laser powers. The phase transformation behavior, tensile properties and shape memory response before and after heat treating were also investigated. The Ni47Ti44Nb9 LPBF alloys have good shaping properties, though a few defects were discovered. Phase transformation peaks did not appear in the as-built samples, but were observed in the heat-treated samples. The phase transformation temperatures of the heat-treated samples increase with the increase in laser power. The tension test at room temperature indicates that the LPBF samples exhibit poor tensile ductility, which may be related to the existence of pores and Ti2Ni or Ti4Ni2Ox phase during the LPBF process. However, the LPBF samples after heat treating still possess good shape memory effect (with recovery strain about 7.82–8%) and relatively high reverse transformation temperature (about 36–52.6 °C) when deformed to 8%.
