微细金属Z-pin对复合材料开孔板压缩性能的影响

Effect of fine metallic Z-pin on compressive property of open-hole composite laminate

通过开孔板压缩试验和建立的参数化多尺度有限元模型,获得微细(φ0.11 mm)金属Z-pin植入体积分数和排布方式对开孔板压缩力学性能和失效行为的影响规律.采用离散实体单元代表Z-pin,选用3D Hashin失效准则判断面内起始损伤,可以有效地模拟结构失效过程中扭结现象的不稳定扩展.结果表明,所有加Z-pin开孔板的压缩强度均低于无Z-pin试样.随着Z-pin植入体积分数的增加,Z-pin与层合板之间的桥联作用增强,加Z-pin开孔层合板压缩强度增加,开孔周围分层损伤区域受到抑制,损伤区域面积最高减小了67%.在相同的体积分数下,Z-pin排布变化对开孔板压缩强度没有显著影响.加Z-pin开孔板有限元模型的模拟结果与试验结果之间的最大相对误差为8.6%.

The influence of fine(ϕ0.11 mm)metallic Z-pin volume fraction and arrangement on the mechanical performance and failure behavior of the open-hole laminates compression was analyzed through open-hole compression test and parametric multi-scale finite element model.Discrete solid element was employed to represent Z-pins,and the 3D Hashin failure criterion was utilized to assess the initial in-plane damage.Then the unstable propagation of kink band was effectively simulated during structural failure.Results showed that the compressive strength of all Z-pinned open-hole laminates was lower than that of specimens without Z-pins.The bridging effect between Z-pins and laminates was enhanced with an increase in Z-pin volume fraction,resulting in increased compressive strength of Z-pinned open-hole laminates.The delaminated area around the hole was suppressed,leading to a maximum reduction of 67%in the damaged area.The variation of Z-pin arrangement did not significantly affect the compression strength of open-hole laminates under the same volume fraction.The maximum relative error between the finite element model simulated results of Z-pinned open-hole laminates and experimental results was 8.6%.