A review on recent developments in fused deposition modeling and large-scale direct pellet extrusion of polymer composites
SungEun, Kim (2020)
2020
All rights reserved. This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited.
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:amk-2020102121476
https://urn.fi/URN:NBN:fi:amk-2020102121476
Tiivistelmä
Fused deposition modeling (FDM) and large-scale direct pellet extrusion has a potential on reducing material waste, energy consumption, and processing time compared to traditional manufacturing processes. However, these technologies deliver end parts with low mechanical properties resulting in failure when under load. In recent years, studies on improving the mechanical properties of printed parts has increased.
In this thesis, recent developments (2000-2020) in FDM and large-scale pellet extrusion of polymer composites are reviewed. To give a better understanding, FDM principle, feedstock materials, and main factors affecting the mechanical properties are described. Processing information such as input material, process equipment, process method, process temperature, nozzle diameter, and process parameters of each literature are tabulated and its influence on the end parts is described in the text. Tested process parameters such as type of reinforcing filler, filler infill, printing angle, printing width, printing layer height were also tabulated, and its effects were explained in the text.
Depending on the reinforced composite different effects on mechanical properties are shown. Increase of filler infill resulted in higher tensile properties and decrease of flexibility. However, after was reached of optimum value, this effect started to decrease. Structures produced in horizontal printing angle (0°), lower printing width, and lower printing height tend to show better mechanical properties. Large-scale production showed higher void formation, shrinkage, and residual stress than small-scale production leading to lower mechanical properties. These factors were reduced with extra process methods such as z-tamping, steel rod post-tensioning, pressure adjusting, compression wheel, MELT CORE printing head, in-box platform, water cooling system, vacuum robot, and nozzle with flexible head.
The concluded analysis of the reviewed literature only allows a general estimation. The collected literature had limitations to accurately compare the printed test specimens due to different process conditions and process parameters. The objective of future research would be to collect further literature with exact overlapping process conditions and process parameters for a better comparison.
In this thesis, recent developments (2000-2020) in FDM and large-scale pellet extrusion of polymer composites are reviewed. To give a better understanding, FDM principle, feedstock materials, and main factors affecting the mechanical properties are described. Processing information such as input material, process equipment, process method, process temperature, nozzle diameter, and process parameters of each literature are tabulated and its influence on the end parts is described in the text. Tested process parameters such as type of reinforcing filler, filler infill, printing angle, printing width, printing layer height were also tabulated, and its effects were explained in the text.
Depending on the reinforced composite different effects on mechanical properties are shown. Increase of filler infill resulted in higher tensile properties and decrease of flexibility. However, after was reached of optimum value, this effect started to decrease. Structures produced in horizontal printing angle (0°), lower printing width, and lower printing height tend to show better mechanical properties. Large-scale production showed higher void formation, shrinkage, and residual stress than small-scale production leading to lower mechanical properties. These factors were reduced with extra process methods such as z-tamping, steel rod post-tensioning, pressure adjusting, compression wheel, MELT CORE printing head, in-box platform, water cooling system, vacuum robot, and nozzle with flexible head.
The concluded analysis of the reviewed literature only allows a general estimation. The collected literature had limitations to accurately compare the printed test specimens due to different process conditions and process parameters. The objective of future research would be to collect further literature with exact overlapping process conditions and process parameters for a better comparison.