Document Type : Research Paper

Authors

Department of Mechanical Engineering, Tarbiat Modares University, Tehran, Iran.

Abstract

3D printing technology is one of the new manufacturing methods that can be used to build folding structures. Folding structures are made flat and deformed into three-dimensional shapes by an actuator. FDM process is one of the most common and cheap 3D printing processes that in this study, the most effective parameters of this process were investigated. For this purpose, the optimal values of printing parameters including printing pattern, thickness of each layer, filling percentage and nozzle temperature to achieve maximum deformation (curvature) were determined by Taguchi experiment design. Then, by adjusting these parameters, the effect of printing speed and total thickness on curvature was investigated. The results showed that with increasing printing speed, the curvature increases and with increasing the total thickness, the curvature decreases. Also, assuming that the curvature is only due to thermal changes, the relationships were extracted using the classical layer theory and compared with the experimental results. This comparison showed that thermal changes alone are not the only cause of curvature and other factors such as residual stresses and shape memory seem to be involved.

Keywords

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