Vidakis Nectarios, Petousis Markos, Velidakis Emmanouil, Liebscher Marco, Mechtcherine Viktor, Tzounis Lazaros
Mechanical Engineering Department, Hellenic Mediterranean University, 71410 Heraklion, Greece.
Institute of Construction Materials, Technische Universität Dresden, DE-01062 Dresden, Germany.
Polymers (Basel). 2020 Dec 6;12(12):2924. doi: 10.3390/polym12122924.
In this study, the strain rate sensitivity of five different thermoplastic polymers processed via Fused Filament Fabrication (FFF) Additive Manufacturing (AM) is reported. Namely, Polylactic Acid (PLA), Acrylonitrile-Butadiene-Styrene (ABS), Polyethylene Terephthalate Glycol (PETG), Polyamide 6 (PA6), and Polypropylene (PP) were thoroughly investigated under static tensile loading conditions at different strain rates. Strain rates have been selected representing the most common applications of polymeric materials manufactured by Three-Dimensional (3D) Printing. Each polymer was exposed to five different strain rates in order to elucidate the dependency and sensitivity of the tensile properties, i.e., stiffness, strength, and toughness on the applied strain rate. Scanning Electron Microscopy (SEM) was employed to investigate the 3D printed samples' fractured surfaces, as a means to derive important information regarding the fracture process, the type of fracture (brittle or ductile), as well as correlate the fractured surface characteristics with the mechanical response under certain strain rate conditions. An Expectation-Maximization (EM) analysis was carried out. Finally, a comparison is presented calculating the strain rate sensitivity index "m" and toughness of all materials at the different applied strain rates.
在本研究中，报告了通过熔融长丝制造（FFF）增材制造（AM）加工的五种不同热塑性聚合物的应变速率敏感性。具体而言，聚乳酸（PLA）、丙烯腈-丁二烯-苯乙烯（ABS）、聚对苯二甲酸乙二醇酯（PETG）、聚酰胺6（PA6）和聚丙烯（PP）在不同应变速率的静态拉伸加载条件下进行了深入研究。所选择的应变速率代表了通过三维（3D）打印制造的聚合物材料的最常见应用。每种聚合物都暴露于五种不同的应变速率下，以阐明拉伸性能（即刚度、强度和韧性）对应用应变速率的依赖性和敏感性。采用扫描电子显微镜（SEM）研究3D打印样品的断裂表面，以此获取有关断裂过程、断裂类型（脆性或韧性）的重要信息，并将断裂表面特征与特定应变速率条件下的力学响应相关联。进行了期望最大化（EM）分析。最后，通过计算不同应用应变速率下所有材料的应变速率敏感性指数“m”和韧性进行了比较。
