热固性树脂基复合材料固化变形影响因素分析

Analysis on factors influencing process-induced deformation for thermoset composites

采用整体-子模块化方法建立了描述复合材料固化全过程的三维有限元模型。以L形层合板为例,分析了固化工艺、结构设计和模具等因素对固化变形的影响方式和程度。数值模拟结果表明:升温速率和对流换热系数通过改变峰值温度影响回弹角,固化压力通过改变树脂分布和含量影响回弹角;铺层方向引起的结构力学性能的变化是回弹角差异较大的主要原因,厚度对固化变形的影响需考虑其对峰值温度和结构刚度变化两方面因素的综合影响,拐角半径的变化对固化变形的影响较小;模具形式通过改变树脂分布梯度和模具对结构的作用力位置影响回弹角,模具材料和形式的选择对于固化变形控制具有重要意义。

By integrated sub-model approach, a three-dimensional finite element analysis （FEA） model was developed to simulate the cure process and predict the process-induced deformation for thermoset composites. L shape structure cure process was simulated to analyze the effect of these cure process parameters on the process- induced deformation. The simulation results show： The heating- rate and convection coefficient influence the deformation by changing peak temperature; cure pressure affects the deformation by changing resin distribution and fiber volume fraction; the ply direction induced mechanical property difference is the main reason of the spring-in angle diversity; the influence of thickness should consider its effect on peak temperature and structure stiffness; the radius has a little influence on deformation; the mold style changes resin distribution gradient direction and mold force position; selection of mold materials and style has crucial influence on the process-induced deformation control.