注塑成型纤维增强热塑性树脂复合材料刚度预测方法  

Stiffness prediction for injection molded fiber reinforced thermoplastics composite

作　　者：黄达勇 赵先琼[1] HUANG Dayong;ZHAO Xianqiong(College of Mechanical and Electrical Engineering,Central South University,Changsha 410083,China)

机构地区：[1]中南大学机电工程学院,长沙410083

出　　处：《复合材料学报》2021年第7期2196-2206,共11页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(51374241)。

摘　　要：基于Hsueh模型的应力场分布,采用代表性体积单元(RVE)平均近似方法,推导出可以退化成Halpin-Tsai模型的泊松比ν_(12)的显性表达式,与桥联模型基本重合。结合Fu模型和Giner模型,引入与纤维长径比(l/a)相关的指数衰减函数得到横向模量E_(22)修正的Halpin-Tsai模型,与自洽模型重合。基于泊松比各向同性假设而推导出的泊松比ν_(23)与有限元结果逼近,远优于Halpin-Tsai模型;基于逆向工程,修正了被Halpin-Tsai模型低估的剪切模量G_(23)。基于经典的层合板分析方法(LAA),引入纤维长度分布(FLD)及纤维取向广义分布函数,对两种注塑成型短玻璃纤维增强热塑性树脂(FRT)复合材料的弹性常数进行预测。结果表明:4个微观力学组合模型均很好地预测了复合材料的弹性常数,但纤维长度质量分布的预测结果比纤维长度数量分布的结果更为合理,特别是对于纵向杨氏模量EL的改进效果大于5%。Based on the stress distribution in representative volume element(RVE)for Hsueh model,the explicit expression of Poisson’s ratioν_(12),which can be reduced to the Halpin-Tsai model,was derived from average approximation method,and it basically coincides with the Bridging model.The modified Halpin-Tsai model for transverse modulus E_(22) was developed by introducing an exponential decay function of l/a related to the Fu and Giner models,and coincides with the self-consistent model.Based on the assumption of Poisson’s ratio properties,the deduced results better than the Halpin-Tsai model are close to the finite element results for Poisson’s ratioν_(23),and then the underestimation of shear modulus G_(23) was corrected by the modified Halpin-Tsai model forν_(23) based on reverse engineering.Based on the laminate analogy approach(LAA)in conjunction with fiber length distribution(FLD)and generalized fiber orientation distribution(FOD)functions,the elastic moduli for two kinds of injection molded short glass fiber reinforced thermoplastics(FRT)composite were predicted.The results show that the four combined micromechanical models all predict the elastic moduli of the composites well,but the prediction results of weight distribution of fiber lengths are more reasonable than that of number distribution of fiber lengths,especially more than 5%in the improvement effect of longitudinal Young’s modulus EL.

关 键 词：刚度预测 微观力学 层合板分析方法(LAA) 纤维增强热塑性复合材料 纤维长度分布(FLD) 纤维取向分布(FOD) 

分 类 号：TB332[一般工业技术—材料科学与工程]