打印层厚度及路径宽度对熔丝成型结合颈的影响规律研究

Theoretical and Experimental Study on the Bonding Neck of Fused Filament Fabrication Parts

熔丝成型(Fused-filament fabrication,FFF)是当今应用最广泛的3D打印技术之一,构成FFF产品的挤出材料丝之间的结合颈对其成型质量及机械性能有着至关重要的影响,然而相应的机理仍不明确。将理论与试验相结合,针对不同打印层厚度及路径宽度对FFF样件结合颈的影响规律进行研究,首先基于挤出材料丝的黏性烧结现象创建结合颈的理论模型;然后,完成FFF样件的制备以及试验准备工作,进而使用扫描电子显微镜(Scanning electron microscope,SEM)对样件的结合颈进行分析及测量;最后,对比分析理论与试验结果,确定打印层厚度及路径宽度对FFF样件结合颈的影响规律,验证理论模型的正确性。结果表明增大打印层厚度会增大纵向结合颈,减小横向结合颈;而增大路径宽度可以增大横向结合颈,减小纵向结合颈。总体上,增大打印层厚度或路径宽度可以提高FFF样件的层间结合质量,并阐明相应的机理。研究成果将为FFF技术在改善成型质量方面提供理论参考和技术支持。

Fused filament fabrication(Fused-filament fabrication,FFF)is one of the most widely used 3D printing technologies,and the bonding neck between the adjoining material filaments of FFF products has an important influence on its forming quality and mechanical properties,but the corresponding mechanism is not clear.Combining theoretical and experimental analysis,the effect of different layer thickness and extrusion width on the FFF parts’bonding neck is studied.Firstly,the theoretical model of the bonding neck is established based on the viscous sintering phenomenon of the extruded filament;The preparation of the samples is then completed,and the bonding neck of the samples is observed and measured by scanning electron microscope(SEM);Finally,the theoretical and experimental results are compared and analyzed,determining the influencing rule of the layer thickness and extrusion width on the built samples’bonding neck,and verifying the correctness of the theoretical model.The results show that increasing the layer thickness will increase the longitudinal bonding neck,but reduce the horizontal one;While for the extrusion width,the situation is in vise versa.In general,the FFF products’bonding quality is improved with the increasing layer thickness or extrusion width,and the mechanism is revealed.The research findings will provide theoretical reference and technical support for FFF technology in improving forming quality.