Laser beam powder bed fusion of nitinol shape memory alloy (SMA)

This study is focused on the 3D printing of NiTi shape memory alloy (SMA) in cuboidal shaped samples via the Laser Powder Bed Fusion (L-PBF) process using a dissimilar material build plate of 316L stainless steel. Four processing parameters were investigated at three levels for the optimization of the process. Those parameters were the laser beam power, scanning speed, laser beam spot size and hatch spacing. The produced samples exhibited varying levels of bonding with the substrate. Compression testing, Archimedes density measurement and EDX chemical composition were carried out. A design of experiment model was developed relating the input process parameters to the output properties. The effect of the calculated volumetric energy density and the sample melt-pool temperatures on the output measures were also investigated for the strong bonding and weldability with the substrate metal. (c) 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Automated summary

This study aimed to 3D print NiTi shape memory alloy in cuboidal shaped samples via L-PBF process using a dissimilar material build plate. Four processing parameters were investigated for process optimization, and the samples were tested for bonding with the substrate. The study also looked into the effect of energy density and melt-pool temperatures on bonding and weldability with the substrate metal.