短纤维增强树脂基复合材料强度和模量的各向异性

Strength and modulus anisotropy of short fiber reinforced polymer composites

研究了短纤维增强聚合物复合材料(SFRP)的强度和模量的各向异性。纤维的平均长度l_(mean)对纤维增强有效因子有很大的影响。在Φ=0°,纤维增强有效因子随着l_(mean)的增加而增加;当Φ=90°,纤维有效因子在Θ不太大时随着l_(mean)增加而增加,当Θ很大时,纤维有效因子值变成零。θ_(mean)对纤维有效因子也有很重要的影响。在Φ=0°,Θ不太大(<40°)时,纤维有效因子随着θ_(mean)增加而减小;而当Θ很大(>50°)时,则随着θ_(mean)的增加而增大。在Φ=90°,Θ不太大时,纤维有效因子随着θ_(mean)增加而减小;而当Θ很大时,纤维有效因子值为零。模式纤维长度对复合材料的强度无明显影响。大l_(mean)对应高的复合材料模量。当Θ接近60°时,平均纤维长度对模量的影响不大。模式纤维长度对模量的影响相对比较小,而对于一个很小的l_(mean),影响则比较明显。当Θ很小时,θ_(mean)值越小,模量值越高;相反,Θ很大时,θ_(mean)值越小,模量值越低。

Short-fiber-reinforced polymer (SFRP) composites have been used for many years because of their superior mechanical properties over corresponding parent polymer matrices and low cost injection molding fabrication technique. Owing to their complex microstructure, especially related to fiber length and orientation distribution, the understanding of strength and modulus of SFRP composites has not been well established. This paper has studied the strength and modulus anisotropy of SFRP composites, making the strength and modulus as a function of loading direction and taking the effects of fiber length and orientation distribution into consideration.