CFRP/AA6061缠绕组合薄壁结构轴向压溃仿真方法

Simulation Method for CFRP/AA6061 Thin-Walled Structure Subjected to Axial Crushing

采用LSDYNA软件建立碳纤维复合材料缠绕在铝合金管外壁组合而成的CFRP/AA6061组合管的模型,对压溃仿真方法进行研究.采用MAT54和MAT123材料模型分别模拟CFRP和AA6061的本构关系,采用参数校准的方法确定CFRP与AA6061的连接界面法向失效应力和切向失效应力,并采用tiebreak接触定义界面.对不同纤维铺层角度的组合结构进行了压溃试验和仿真模型验证.结果表明,该仿真模型精度较高,对[0/90]3和[90]6铺层组合管的峰值载荷仿真误差分别为8%和11.2%,均值载荷误差分别为8.7%和6.7%,仿真结果较准确地再现了压溃过程中的峰值载荷和均值载荷,该仿真模型可用于CFRP/金属组合薄壁结构的压溃试验与仿真研究.

Firstly,using LSDYNA software,a CFRP/AA6061 composite tube model was established with CFRP wrapped around the outer wall of aluminum alloy tube to study suitable crushing simulation method.And then,the MAT54 and MAT123 material models were used respectively to simulate the constitutive relation of CFRP and AA6061.The normal failure stress and shear failure stress at the interface between CFRP and AA6061 were determined by calibrating parameters,and the interface was defined according to tiebreak contact type.Finally,taking the composite structure with different angle fiber layers as the object,a crush test was carried out to validate the simulation model.The results show that,the simulation model constructed in this paper presents high precision and can reflect well the peak crush force and mean crush force during the test.The simulation error of[0/90]3 and[90]6 layer composite tube can reach 8%and 11.2%respectively for peak crush force,8.7%and 6.7%respectively for mean crush force.This model can also simulate the axial crushing performance and failure mode of the composite structure.This model can be used for the crushing test and simulation study of CFRP/aluminum alloy composite thin-walled structures.