基于PAM-RTM的CFRP平板RTM工艺及孔隙缺陷仿真

Simulation of RTM process and void defect for CFRP flat plate based on PAM-RTM

树脂传递模塑(RTM)成型过程中不同工艺参数对碳纤维增强树脂基复合材料(CFRP)构件质量和性能有极大影响。为了精准设计RTM成型参数,降低最终构件的孔隙缺陷含量,分析充模过程中两种尺度孔隙率的变化及在构件中的分布规律,基于PAM-RTM软件对CFRP平板模型RTM成型的充模及双尺度孔隙形成进行了仿真模拟。分析了不同树脂黏度、浇注压力对填充时间及宏观和微观孔隙分布、孔隙率的影响规律;在构件中选取了不同位置的横向轴线并对比轴上宏观/微观孔隙的含量及分布特征,分析随着距离浇注口位置变化孔隙率的变化规律。结果表明,在恒压浇注条件下,浇注压力越大,树脂黏度越小,填充时间越短;树脂黏度为0.1Pa·s、浇注压力为1.5MPa时,充模时间最小,为13.11s。宏观孔隙率随浇注压力升高而减小,微观孔隙率则相反。宏观孔隙在开始填充一段时间后形成,孔隙率最终在出胶口达到最大值;微观孔隙则在填充初始阶段开始形成,孔隙率随着填充距离增加逐渐减小。3条横向轴上两种尺度孔隙率的变化趋势相近;浇注压力影响宏观孔隙开始形成的位置及微观孔隙结束形成的位置,并影响填充结束时的最大宏观孔隙率和填充开始时的最大微观孔隙率。

Different process parameters during resin transfer molding(RTM)molding have a great influence on the quality and performance of carbon fiber reinforced resin-based composite(CFRP)components.In order to accurately design the RTM molding parameters,reduce the void defect content of the final components,and analyze the changes of two-scale void content during the mold filling process and the distribution law in the components,the mold filling and two-scale void formation of CFRP flat plate model RTM molding were simulated based on PAM-RTM software.The influence of different resin viscosity and injection pressure on the filling time,macro and micro void distribution and content were analyzed.The transverse axes at different positions in the components were selected and the macro/micro void content was compared and characteristics on the axes to analyze the change rule of void content with the change of the position from the injection port were distributed.The results show that,under the condi‐tion of constant pressure injection,the higher the injection pressure,the lower the resin viscosity and the shorter the filling time;when the resin viscosity is 0.1 Pa·s and the injection pressure is 1.5 MPa,the mold filling time is the smallest,which is 13.11 s.The macro void content decreases with the increase of injection pressure,while the micro void content is the opposite.Macro void is formed after a period of time at the beginning of filling,and void content finally reaches the maximum value at the outlet.Micro void is formed at the initial stage of filling,and void content gradually decreases with the increase of filling distance.The trends of the two scales of void content on the three transverse axes are similar,the injection pressure affects the location of the beginning of the formation of macro void and the end of the formation of micro void,and affects the maximum macro void content at the end of filling,and the maximum micro void content at the beginning of filling.