Laser Powder Bed Fusion of Sinusoidal Lattice Structure Using Shape Memory Alloys

Lattice structures possess remarkable mechanical characteristics including lightweight, high specific strength, and large energy absorption capacity. When made of shape memory alloys (SMA), lattice structures can exhibit unique mechanical performance and reusability. In the fabrication of these complex geometry structures, powder bed fusion (PBF) offers advantages over traditional methods. This work proposes an optimized design of body-centered-cubic (BCC) lattice structure based on sinusoidal curves. Based on computational analysis, the proposed sinusoidal lattice structure demonstrates an 8.2% increase in stiffness, with an improved stress distribution under compressive loads. To validate the proposed design, a prototype of this design is fabricated using SMA via PBF and subjected to cyclic loading and impact tests. The experiment results highlight the improvement in fracture resistance and load-bearing capacity attributable to the large contact area within the proposed configuration. The prototype also demonstrates exceptional shape memory effect and superelasticity, achieving a recovery rate of 98% after heat treatment. Additionally, the use of SMA material enables the structure's multifunction in energy absorption, impact resistance, and vibration isolations, making it an excellent candidate for applications in aerospace and automotive industries. This work introduces an optimized design for a body-centered-cubic lattice structure using shape memory alloys and powder bed fusion fabrication. The design, based on sinusoidal curves, shows an 8.2% increase in stiffness and improved stress distribution, with exceptional shape memory effect, fracture resistance, and load-bearing capacity, making it ideal for aerospace and automotive applications.image (c) 2024 WILEY-VCH GmbH