Theoretical Study on the Apparent Viscosity of Melt Inside the Fused Filament Fabrication Extrusion Liquefier Under Vibration Field

doi:10.12068/j.issn.1005-3026.2021.03.014

Abstract

Abstract: The apparent viscosity of the melt inside the extrusion liquefier is one of the key factors affecting the mechanical properties of fused filament fabrication (FFF) products. A method applying a longitudinal sinusoidal vibration to the FFF extrusion liquefier is proposed to improve the apparent viscosity of the internal melt. Then the theoretical model of the apparent viscosity of the melt inside the extrusion liquefier with vibration applied is carried out， and the experimental results from the existing literature are used to verify the correctness of the theoretical model. Finally， the variation of apparent viscosity with different-frequency vibrations applied is discussed through the model， and the corresponding mechanism is clarified. It is shown that the theoretical results agree well with the experimental ones，validating the model’s feasibility. When the vibration field is applied to the extrusion liquefier， the effective value of apparent viscosity will decrease with the increase of vibration frequency.

Key words: fused filament fabrication(FFF); extrusion liquefier; vibration; apparent viscosity; theoretical model

CLC Number:

TH113.1

JIANG Shi-jie， CHEN Pi-feng， SUN Ming-yu， DONG Tian-kuo. Theoretical Study on the Apparent Viscosity of Melt Inside the Fused Filament Fabrication Extrusion Liquefier Under Vibration Field[J]. Journal of Northeastern University(Natural Science), 2021, 42(3): 395-401.

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