Volume Fraction Effect on the Mechanical and Shape Memory Properties of NiTi Gyroid Lattice Structure Fabricated by Laser Powder Bed Fusion

The triply periodic minimal surface (TPMS) structure of NiTi has gained significant attention owing to its potential for reusable buffer devices. However, the manufactured NiTi TPMS structure still faces challenges such as uneven pore distribution and numerous internal defects, primarily because of the lack of a design theory. Laser powder bed fusion technology has emerged as a promising approach for producing NiTi alloys and TPMS structures, affording substantial advantages. Thus, this study focused on designing and manufacturing three volume-fraction sheeted gyroid lattice structures by using laser powder bed fusion technology. Among the three structures, the VF15 gyroid lattice structure demonstrates the highest values for the compressive modulus (741.42 MPa), nominal yield strength (42.26 MPa), and ultimate yield strength (152.21 MPa). The findings highlight the effectiveness of laser powder bed fusion in preparing NiTi TPMS structures. In general, the utilization of laser powder bed fusion technology for fabricating NiTi TPMS structures combines the strengths of both the NiTi alloy and TPMS structures, resulting in outstanding buffering and shape memory capabilities. Therefore, the findings have potential applicability in efficient and secure reversible energy absorption devices.