Flexural Properties of 3D Printed Continuous Fiber Reinforced Resin T-beams
WU Siyuan1,2, SHAN Zhongde1,3,*, CHEN Ken2, LIU Feng1, LIU Xiaojun1, YAN Chunhui1
1 State Key Laboratory of Advanced Forming Technology and Equipment, China Academy of Machinery Science & Technology Group Co., Ltd., Beijing 100048, China 2 Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China 3 College of Mechanical & Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
Abstract: The continuous fiber reinforced resin 3D printing based on fused deposition technology offers a new rapid prototyping method for the fabrication of beam structures. It is also highly designable and enables the forming of lightweight and multifunctional beam structures. In this work, the flexural performance of T-beams with 0 mm and 5 mm rib heights at different printing parameters were tested. The flexural strengths and modulus of T-beams were investigated for print thicknesses of 0.7 mm, 0.8 mm and 0.9 mm and print spacing of 0.6 mm, 0.7 mm and 0.8 mm. At the same time, the acoustic emission technology was used to test and analyze the flexural failure process of the T-beam. The research utilized principal component analysis method and K-means++clustering algorithm to classify the collected signal damage. The results indicate that within the thickness of 0.7—0.9 mm, the flexural strength and modulus of the T-beam decrease with the increase of the thickness of the printing layer. Within the 0.6—0.8 mm spacing between the printing filaments, with the increase in the spacing between the printing filaments, the flexural strength and modulus of the T-beam also decrease correspondingly. From the initial loading of the T-beam to the failure stage of failure, the corresponding characteristic signals can be clustered into five categories. Corresponding to five failure modes, namely matrix cracking, interlayer debonding, fiber and resin debonding, fiber cracking and fiber fracture, the classification results can explain the failure process well.