碳纤维-不锈钢层板热载条件下冲击动态响应及层间损伤仿真研究

Numerical Simulation of Impact Dynamic Responses and Interlayer Failure of CFRMLs Under Thermal Loads

为了研究碳纤维不锈钢层板的冲击动态响应以及热载荷条件下的冲击性能,采用ABAQUS/Explicit,编写基于复合材料渐进损伤用户子程序VUMAT;引入Johnson-Cook模型,仿真计算了碳纤维增强环氧树脂基复合材料-SS304不锈钢层板热载条件下冲击动态响应过程;分析了其冲击动态响应及渐进损伤,着重讨论了热载荷条件对碳纤维金属层板的冲击能量吸收、接触力等抗冲击性能及失效模式的影响.结果显示,高速冲击载荷作用下,纤维层的脆性断裂、金属层的塑性变形以及纤维层与金属层之间的脱层是碳纤维不锈钢层板的主要失效形式.热载荷的存在直接影响了冲头的接触力,随环境温度升高,接触力总体上降低,子弹的速度衰减越慢,剩余速度增大.结果表明,热载荷降低了纤维金属板的冲击动能吸收特性,弱化了碳纤维金属板的抗冲击性能.无论是纤维金属层板的整体破坏,还是纤维失效、基体失效和脱层失效,热载荷都产生了重要影响.

To investigate the impact response characteristics of carbon fiber reinforced metal laminates （CFRMLs） and the effects of thermal loads on the impact performance of CFRMLs, the VUMAT user subroutine for composite progressive damage modes and the Johnson-Cook model based on ABAQUS/Explicit were employed to simulate the impact response process of carbon fiber reinforced epoxy resin matrix composite-stainless steel laminates under different ambient temperatures. The dynamic responses and damage evolution of CFRMLs were dis- cussed. The effects of thermal loads on the kinetic energy absorption, the contact force and the failure modes of CFRMLs were analyzed detailedly. The results show that the main failure forms of CFRMLS under high-speed impact loads involve the brittle fracture of carbon fiber layers, the plastic deformation of metal layers and the delamination between carbon fiber layers and metal layers. The thermal load has significant effects on the impact performance of CFRMLs. The re- sidual bullet velocity and the contact force between the bullet and CFRMLs are directly influ- enced by the thermal load. In general, with the rise of the ambient temperature, the contact force decreases while the residual bullet velocity increases. This indicates that the thermal load rise reduces the kinetic energy absorption capability of CFRMLs, and weakens the anti-impact performance of CFRMLs. The thermal load also has great effects on the global failure, fiber fail- ure, matrix failure and delamination of CFRMLs during the impact process.