4D printing using FDM

• Main Author: Dinesh, Konnur Ashwin
• Other Authors: Hortense Le Ferrand
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2021
• Subjects: Engineering::Mechanical engineering
• Online Access: https://hdl.handle.net/10356/151195
• Institution: Nanyang Technological University

Three - Dimensional (3D) printing or additive printing is becoming an increasing trend in manufacturing industries due to its versatility and its ability to manufacture components of complex geometries. CAD modelling is used in making the product. The term 3D printing refers to different processes in which material is deposited, assembled, or solidified to create a three-dimensional object, with the material being added layer by layer. In four - dimensional (4D) printing, time is the additional dimension, which allows a printed sample to change its shape over a matter of time. In layman’s term, the filament is inserted into the fused deposition modelling (FDM) printer which melts the filament and squeezes it out from the nozzle before depositing the samples onto the printer bed. These samples are built layer by layer which fuses well and upon cooling the final product is formed. The aim of this study is to explore on how morphing can be achieved in FDM printing. The most popular choices of printing material for FDM are acrylonitrile butadiene styrene (ABS) and Polylactic Acid (PLA) known for its shape memory properties. However, PLA is used throughout all the experiments. The material is melted slightly above its glass transition temperature (Tg) and then extruded in a pattern on top of previous extrusions, creating an object layer by layer. These chains would then uncoil itself to relieve those pre-stress. Through this research various infill density, temperature of nozzle, speed of nozzle and bed temperature are experimented to study the morphing effects of 3D printed PLA samples. Each parameter is studied extensively to optimize the overall objective. Infill density of 25 %, 50 %, 75 % and 100%. Temperature of nozzle at 195 °C, 207 °C, 219 °C and 230 °C. Speed of nozzle at 30 mm/s, 45 mm/s, 60 mm/s and 70 mm/s. Bed temperature at 20 °C, 40 °C and 60 °C. Morphing of the samples were conducted for the various parameters to analyse the curvature of the samples. Various parameter optimization was one of the many ways to achieve morphing, however future works will be examined through other parameters and software as well.