多向GF/CF混杂复合材料拉压力学性能研究

Tensile and Compression Properties of Multi-directional Carbon/Glass Fiber Hybrid Composite

采用工程上常用的铺层角度,设计7组不同的铺层方式,通过拉伸与压缩实验研究了多向玻璃纤维(GF)/碳纤维(CF)混杂复合材料的拉伸和压缩性能,得到了拉伸与压缩过程中力–位移曲线图及相应的破坏形貌。提出了铺层角度混杂比(CF相对体积分数)的概念,研究了不同铺层角度的混杂比对复合材料拉伸和压缩性能的影响。结果表明,多向纤维混杂复合材料的拉伸与压缩性能与总混杂比无明显关系,而与不同铺层角度各自的混杂比有关。其中,0°铺层混杂比对其影响最大,90°铺层混杂比影响最小,±45°铺层混杂比的影响介于两者之间。当0°铺层混杂比为100%时,复合材料的拉伸与压缩性能最高,拉伸破坏表现为一次破坏,破坏时层间分离的程度最低;当0°铺层混杂比低于100%时,复合材料的拉伸破坏表现为二次破坏。复合材料的压缩破坏大多表现为一次破坏,且在破坏时GF的破坏大多表现为"屈曲失稳"的形式,从而减缓了CF的脆性断裂程度。

Seven group lay-up means were designed using common lay-up angle in in engineering and the tensile and compression properties of multi-directional hybrid composites reinforced by glass fiber （GF） and carbon fiber （CF） were gained, the force-displacement curves and corresponding damage morphology were got by experimental research. A conception of lay-up angle hybrid ratio （the relative volume fraction of CF） was proposed and the influences of different lay-up angle hybrid ratio on the tensile elastic modulus, tensile strength, compression elastic modulus and compression strength of the composites were also studied. The results show that the tensile and compression properties of the composites have little relation with the total hybrid ratio, but are related to the angle hybrid ratio. Among which, the 0° hybrid ratio affects the properties the most while 90° hybrid ratio the least, 45° hybrid ratio is between both. When the 0° hybrid ratio reaches 100%, both the tensile and compression properties of the composites show the best, it＇ s fracture mode is disposable damage and delamination is not the most obvious. When the 0° hybrid ratio is lower than 100%, the tensile failure mode turns out to be a secondary damage. Most of the compression failure modes are disposable damage. The fracture of most GF is buckling so that the brittle fracture of CF is slowed down.