熔融沉积成形锰锌铁氧体/聚乳酸复合材料的力学和吸波性能

Mechanical and microwave absorbing properties of Mn-Zn ferrite/polylactic acid composites formed by fused deposition modeling

3D打印技术在快速制造复杂形状零件方面获得了越来越多的关注。将锰锌铁氧体(MZF)作为增强体填充到聚乳酸(PLA)中,通过球磨混合和熔融挤出法制备出MZF/PLA复合线材,利用熔融沉积成形(FDM)制备出MZF/PLA复合材料。采用XRD、SEM和矢量网络分析仪对不同复合比例的MZF/PLA复合材料的微观形貌、力学性能和电磁性能进行表征,并计算不同厚度的反射损耗,研究MZF的含量对复合材料吸波性能的影响。结果表明:当MZF含量为10wt%时,MZF/PLA复合材料的拉伸强度相比纯PLA提升了17.6%,随着MZF含量的提升,复合材料的吸波性能随之增强。当MZF的含量达到50wt%,在12.7 GHz处,厚度为7.4 mm时反射率达到最小值-55.3 dB,在厚度为7.9 mm时,有效吸波频带宽为4.5 GHz。因此,基于FDM制备的3D打印MZF/PLA复合材料具有良好的吸波性能和承载能力,是一种非常有前途的3D打印微波吸收材料。

3D printing technology has received more and more attention in the rapid manufacturing of complex shape parts.Mn-Zn ferrite(MZF)was filled into polylactic acid(PLA)as reinforcement,the MZF/PLA composite wire was prepared by ball milling mixing and melt extrusion,and the MZF/PLA composites was prepared by fused deposition modeling(FDM).The micro morphology,mechanical properties and electromagnetic properties of MZF/PLA composites with different composite ratios were characterized by XRD,SEM and vector network analyzer,and the reflection loss of different thickness was calculated to study the effect of MZF content on the microwave absorption properties of the composites.The results show that when the MZF content is 10wt%,the tensile strength of MZF/PLA composite is 17.6%higher than that of pure PLA.With the increase of MZF content,the microwave absorption performance of the composite enhanced.When the content of MZF reaches 50wt%at 12.7 GHz,when the thickness is 7.4 mm,the reflectivity reaches the minimum value of−55.3 dB,and when the thickness is 7.9 mm,the effective microwave absorption band width is 4.5 GHz.Therefore,the 3D printed MZF/PLA composite prepared based on FDM has good microwave absorbing properties and bearing capacity,and it is a very promising microwave absorbing material for 3D printing.