碳纤维含量对增强尼龙复合材料性能的影响

EFFECT OF CARBON FIBER CONTENT ON PROPERTY OF REINFORCED NYLON COMPOSITE

碳纤维可以提高工程塑料的力学性能,本文研究了碳纤维含量对碳纤维/PA66复合材料性能和增强效率的影响规律,并对其增强的原因进行了分析。采用注塑成型工艺制备了10wt%~40wt%纤维含量的碳纤维/PA66拉伸试样,通过试验获得了增强复合材料的弹性模量和抗拉强度,并与未增强样件进行了对比;分析了碳纤维含量对纤维增强效率的影响,采用扫描电子显微镜(SEM)观察了拉伸试样断面的微观结构。研究表明:碳纤维/PA66的弹性模量随着纤维含量的增加而增大,抗拉强度先增大后下降,峰值出现在纤维含量为30wt%时;碳纤维/PA66复合材料弹性模量的纤维增强效率受碳纤维含量的影响不大,高纤维含量下碳纤维对碳纤维/PA66复合材料抗拉强度的增强效率下降,主要是由于高纤维含量下微观界面强度的减弱和纤维接触概率增大导致的界面缺陷。本文研究的碳纤维含量对碳纤维/PA66材料力学性能和效率的影响规律,可为增强复合材料的设计提供指导。

Carbon fiber can improve the mechanical properties of engineering plastics. This paper studies the effect of carbon fiber content on the properties and reinforced efficiency of carbon fiber reinforced nylon 66 (CF/PA66) composites, and analyzes the reasons for its enhancement. The CF/PA66 tensile specimens with fiber fraction of 10wt% to 40wt% were prepared by injection molding process. The elastic modulus and tensile strength of the reinforced composites were obtained through experiments and compared with the unreinforced samples. The effect of carbon fiber content on fiber-reinforced efficiency was analyzed. The fracture surface of tensile specimens was observed by scanning electron microscopy (SEM). The results show that the elastic modulus of CF/PA66 increases with the increase of fiber content, the tensile strength increases first and then decreases, and the peak value appears when the fiber content is 30wt%;the fiber-reinforced efficiency of CF/PA66 composites is not affected by carbon fiber content. The high fiber content of carbon fiber has lower tensile strength enhancement of CF/PA66 composites. The main reason is the weakening of micro-interface strength and the interface defect caused by the increase of fiber contact probability under high fiber content. The effect of the carbon fiber content studied on the reinforcing properties and efficiency of carbon fiber/PA66 materials can provide guidance for the design of reinforced composite materials.