An Experimental Study of Low Velocity Impact Damage in Woven Fiber Composites
An Experimental Study of Low Velocity Impact Damage in Woven Fiber Composites
复制标题
DOI：
10.1177/002199839803201203
复制
发表时间：
1998-06
影响因子：
2.9
通讯作者：
Y. Siow;V. Shim
中科院分区：
文献类型：
--
作者：
Y. Siow;V. Shim
研究了编织纤维[0/90，-45/45，0/90]s碳/环氧复合材料板的低速冲击响应和冲击后的力学性能。这补充了许多其他研究人员所做的工作，他们也研究了复合材料的低速冲击，但重点是单向，交叉铺层或准各向同性层压板。在本研究中，冲击后静态单轴拉伸，压缩，以及拉压疲劳试验进行。编织层压板的损伤机制被发现主要是分层和纤维断裂，与冲击引起的分层面积线性增加的冲击能量的范围内检查。损坏程度和类型还取决于撞击器尖端的曲率，尖锐撞击器产生的变形更局限于局部。注意到存在一个阈值能量水平，低于该阈值能量水平时，不会发生由C-扫描辨别的分层。与以前的研究结果相比，据观察，在冲击器减速时间响应的峰值是不相关的纤维故障，这可能会发生更早的发病。因此，当该峰值出现时吸收的能量的量并不表示引发纤维断裂所需的能量。据观察，残余拉伸强度是分层面积和撞击器尖端半径的函数。对于静态压缩和拉压疲劳，残余承载能力仅取决于分层面积。在压缩下，分层促进纤维的微屈曲，而在拉伸下，失效主要是通过纤维断裂。对于一个普通的冲击能量和冲击器，一个损坏的标本是在压缩比拉伸弱。
A study is made on the low velocity impact response and post-impact mechanical capacity of woven fiber [0/90,-45/45,0/90]s carbon epoxy composite plates. This complements the work done by numerous other researchers who have also examined low velocity impact of composites, but have focused on unidirectional, cross-ply or quasi-isotropic laminates. In the present study, post-impact static uniaxial tension, compression, as well as tension-compression fatigue tests are performed. The damage mechanisms for woven laminates are found to be predominantly delamination and fiber breakage, with the area of impact-induced delamination increasing linearly with impact energy for the range of energies examined. Damage extent and type are also dependent on the curvature of the impactor tip and deformation generated by a sharp impactor is more localized. The existence of a threshold energy level below which no delamination discernible by C-scan occurs is noted. In contrast with previous findings, it is observed that the peak in the impactor deceleration-time response is not associated with the onset of fiber failure, which can occur earlier. The amount of energy absorbed when this peak occurs therefore does not indicate the energy required to initiate fiber breakage. It is observed that residual tensile strength is a function of delamination area and impactor tip radius. For static compression and tension-compression fatigue, the residual load-bearing capacity is only dependent on delamination area. Under compression, delamination promotes the micro-buckling of fibers, whereas in tension, failure is predominantly via fiber breakage. For a common impact energy and impactor, a damaged specimen is weaker in compression than in tension.