CF表面改性对3D打印PLA/CF试件力学性能的影响

以短切碳纤维(CF)和聚乳酸(PLA)为实验原料,用硝酸在恒温水浴加热条件下对短切CF进行表面处理,并做表征,结果表明,硝酸处理后短切CF的表面粗糙度显著增大,并且出现了较多的沟槽;硝酸处理后CF(002)和(100)石墨晶面的衍射强度有明显提升,并且CF表面C元素含量相对未处理的有所降低,而O元素和N元素的含量有所提高。在双螺杆挤出造粒机上分别配比CF质量分数为5%的未经硝酸处理和硝酸处理后的PLA/CF粒料颗粒,并在粒料3D打印机上制得两种纤维增强的拉伸、弯曲、冲击试件,研究了短切CF的表面处理对3D打印PLA/CF试件综合力学强度的影响。结果表明,硝酸处理后PLA/CF试件的综合力学性能有明显提升。

Effect of CF Surface Modiifcation on Mechanical Strength of 3D Printing PLA/CF Specimens

Using short carbonfiber (CF) and polylactide (PLA) as experimental materials,the short CF was surface treated with nitric acid under constant temperature water bath heating and the physical characteristics of treated CF was presented. The results showed that the surface roughness of the short CF was significantly increased after nitric acid treatment,and more grooves were found. The diffraction intensity of graphite crystal plane (002) and (100) was obviously improved,and the content of C element on carbonfiber surface was lower than that of untreated,and the contents of O element and N element were improved. The treated and untreated PLA/CF pellets were manufactured by the twin-screw extruder respectively with 5％ CF mass fraction,which were used as the material to print tensile,bending and impact specimens on pellets 3D printer. The effect of CF surface treatment on the comprehensive mechanical strength of 3D printing PLA/CF specimens was studied. The results showed that the comprehensive mechanical strength of PLA/CF specimen after nitric acid treatment was improved obviously.