热塑性复合材料机器人铺放系统设计及工艺优化研究

Design of Robotic Fiber Placement Machine and Process Optimization for Thermoplastic Composites

针对热塑性复合材料的铺放功能及其实际需求,以机器人为载体,开展了热塑性复合材料铺放设备关键技术及工艺优化研究。根据机器人铺放头特点,提出了铺放头总体设计方案,设计了加热、剪断、重送、夹紧、张力调控等功能模块,开发出了电气控制、PID张力控制、温度控制等控制单元,实现热塑性复合材料机器人铺放设备的搭建。采用GF/PP热塑性预浸料,开展工艺对比试验及检测试验,并探究了显微结构对力学性能的影响,结果表明:铺放工艺制备的试样中层与层间有明显区分,且结晶度较低,是造成其力学性能不及真空袋辅助成型的主要原因。采用响应面法优化了铺放工艺参数并进行试验验证,优化后铺放工艺成型构件的缺陷较少,其力学性能与真空袋辅助成型制备的构件相当,从而验证了热塑性复合材料机器人铺放设备的可行性及有效性。

Aiming at the actual demand of thermoplastic composite made by automated fiber placement(AFP),the key techniques and process optimization of AFP machine for thermoplastic composite with the robot as a carrier are studied.Based on the characteristics of the robotic placement head,the overall design plan of the placement head is proposed.Furthermore,the functional modules such as heating,cutting,refeeding,clamping,and tension control are designed.Electrical control,PID tension control,and temperature control are developed respectively.The construction of the AFP machine is realized.Then,process comparison and detection experiments are conducted regarding GF/PP thermoplastic prepreg.The effect of microstructure on mechanical properties is explored.The results show that the samples made by the laying process have a clear distinction from layer to layer and exist a lower crystallinity,which is the main reason that their mechanical properties are inferior to vacuum bag assisted molding.The response surface method was used to optimize the process parameters.Experimental results show that the optimized process have fewer defects,and mechanical properties are comparable to those made by vacuum bag-assisted molding,thus verifying the feasibility and effectiveness of the AFP machine.