Development of continuously varied infill pattern (ConVIP) method in FDM 3D printing

Abstract

Additive manufacturing technology, especially fused deposition modeling, has been used in various fields such as aerospace, automobile, and medical industries. However, low mechanical properties and printing speed remain critical problems that limit the adoption of fused deposition modeling 3D printing. Therefore, this thesis developed a Continuously Varied Infill Pattern (ConVIP) method to improve the mechanical properties and printing speed of printed parts in fused deposition modeling 3D printing. Through ConVIP method, ultimate tensile strength and elongation at break increased by up to 15.2% and 40.3%, respectively, and the printing speed was also improved by up to 29.4%. The improvement of mechanical properties and printing speed was compared with the conventional slicing method, and the results were analyzed through a confocal microscope. The increase in ultimate tensile strength and elongation at break of the tensile specimen was attributed to the increase in the height of the interlayer contact point, and the improvement in the printing speed was confirmed by G-Code that the printing path was optimized. In addition, the amount of material used for tensile specimen printing was consumed up to 8.9% less than the conventional slicer method. This thesis confirmed that Continuously Varied Infill Pattern improved mechanical properties, printing speed, and material use.