Topic: Mechanisms and Challenges in 3D Printing of Carbon Fiber Composites
Speaker: Prof. Ye Lin, Southern University of Science and Technology
Time: Monday, October 23, 2023, 10:00 a.m.
Venue: C708, New Main Building, Xueyuan Road Campus
Abstract:
3D printing enabled by fused filament fabrication (FFF) has been extensively studied in recent years because of its capability for manufacturing continuous fiber composite parts when a matrix-impregnated filament with continuous fibers can be deposited or steered in a desired direction to fully realize the potential of high load-bearing capacity of high strength fibers. The successful fabrication of high quality continuous fiber composite parts using a 3D printing method is secured by completion of a few key mechanisms such as precise deposition of a filament and fusion between a depositing filament and filaments deposited in previous steps, while the fusion is modulated by two key mechanisms of “intimate contact” and “autohesion”. The poor quality of 3D printed polymer or fiber reinforced polymer composite parts made by FFF is resulted from poor or weak fusion between filaments during a 3D printing process, resulting in presence of a high content of voids in a part, which leads to low “intralaminar” and “interlaminar” mechanical performance. This presentation summarizes some recent results on effects of weak or poor fusion on mechanical performance of PA6, short carbon fiber (CF)/PA6, continuous CF/PA6 fabricated using a 3D printing platform. Essential work of fracture (EWF) tests were conducted to characterize the fusion quality between filaments, in both “intralaminar” and “interlaminar” deposition modes, respectively, of printed thin PA6 film and CF/PA6 composite films made by FFF using a double edge notched tension (DENT) method. A mechanistic model is developed to describe “intimate contact” and “autohesion” processes during the “interlaminar” deposition mode, equipped with parameters such as surface profile of depositing filament, temperature of depositing head, contact duration between filaments, contact pressure between filaments, while the latter is measured by a high precision 3D dynamometer instrumented on the 3D printing platform. It is concluded that a high quality depositing filament of a precise diameter and high precision deposition of the filament in a defined path with a tailored processing window of deposition temperature, depositing speed, and deposition pressure are the keys for the successful fabrication of high quality continuous fiber composite parts using 3D printing.
About the Speaker:
Ye Lin is currently a Chair Professor at the School of System Design and Intelligent Manufacturing (SDIM), Southern University of Science and Technology (SUSTech). He received his Bachelor of Engineering from Harbin Engineering University in 1982, Master of Engineering and Ph.D from Beihang University in 1984 and 1987, respectively. He worked as Lecturer at Xi’an Jiao Tong University from 1988 to 1990 before he joined the Institute for Composite Materials (IVW GmbH) at the University of Kaiserslautern in 1990 as an Alexander von Humboldt Research Fellow. He joined the University of Sydney as Lecturer in 1992, and subsequently promoted to Senior Lecturer, Reader and Professor in 2002. Prof. Yereceived the Friedrich Wilhelm Bessel Research Award in 2004 from the Alexandra von Humboldt Foundation, and was elected a Fellow (FTSE) of Australian Academy of Engineering (ATSE) in 2005.
School of Aeronautic Science and Engineering
