The superelastic TiNi alloy can be used in the manufacture of aerospace functional devices

and the method of selective laser melting can obviously improve the freedom and complexity of the design of functional devices. The superelasticity of TiNi is studied through analyzing microstructure of TiNi alloy and condcuting the superelasticity cycling tests. The results show that in 20 times cycling tests

superelasticity behaves well and has a phase transition platform of more than 6% strain

martensitic transformation start and end stress have a small attenuation about 4MPa

phase transformation stress is stable

and the cumulative residual strain is only 1.8%; Under different strain amplitude

the energy consumption in the alloy deformation increases from 23N · mm to 156N · mm

and the energy consumption linearly increases with strain amplitude; The superelastic property of the alloy does not significantly change at different strain rates. Under different loading conditions

the TiNi alloy manufactured by selective laser melting has a more stable superelastic behavior compared with the TiNi alloy manufactured by traditional way

and is more conducive to manufacture the stable functional devices.