Effect of Thickness and Infill Density on Acoustic Performance of 3D Printed Panels made of Natural Fiber Reinforced Composites

ABSTRACT

Additive manufacturing (AM) of Natural Fiber-Reinforced Composites through Fused Deposition Modeling is receiving much attention in recent years. AM is very appealing for complex shape structures that can be inconvenient to produce by other methods. In this study, the acoustic panel made from polylactic acid reinforced with wood fiber composite was 3D printed by varying its thickness and infill density. The sound absorption coefficient was measured using an impedance tube. The thin panel with back air gap was found to absorb sound at mid-frequency range resembling the Helmholtz resonator. The absorption performance for the thick panel can be controlled by controlling the infill density of the panel. Customizing the acoustic absorption is therefore possible for panels from biodegradable materials by AM.

摘要

近年来，通过熔融沉积模型（FDM）实现天然纤维增强复合材料（NFRC）的增材制造（AM）受到了广泛关注. AM对于不方便用其他方法生产的复杂形状结构非常有吸引力. 本研究以聚乳酸（PLA）为基材，以木纤维复合材料为增强材料，藉由改变其厚度及填充密度，制备出具有三维效果的吸声板. 用阻抗管测量吸声系数. 研究发现，带有后气隙的薄板在中频范围内吸收声音，类似于亥姆霍兹谐振器. 厚板的吸声性能可以通过控制填充密度来控制. 因此，通过添加制造，定制可生物降解材料制成的面板的吸声性能是可能的.

关键词:

• 增材制造
• 熔融沉积模型
• 打印生物降解隔音板
• 天然纤维增强复合材料
• 吸声
• 填充密度

KEYWORDS:

• Additive manufacturing
• fused deposition modeling
• 3D printed biodegradable acoustic panel
• natural fiber-reinforced composites
• sound absorption
• infill density

Acknowledgments

The author is thankful to the Taylor’s University for funding scholarship during this research work. An acoustic impedance tube was used in collaboration with Universiti Teknikal Malaysia, Melaka.

Declaration of conflicting interest

The authors declare that there are no conflicts of interest regarding the publication of this paper.

Additional information

Funding

This work was partially sponsored by Taylor’s University Flagship Research Grant TUFR/2017/001/05.