Fracture Mechanics of Interfaces of Laminates Subjected to Thermal Shock or Low Velocity Impacts

热冲击或低速冲击下层压板界面的断裂力学

基本信息

批准号：
17560073
负责人：
TOYA Masayuki
金额：
$ 1.86万
依托单位：
Kagoshima University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2006
项目状态：
已结题

项目摘要

A laminated plate containing an interior disc-shaped interface crack is considered. The main aim of the present research is to derive the energy release rates, which is the most important parameter that determines the condition of interface crack growth.First, we consider the case when a laminated plate is subjected to thermal shock. A constant heat flux is assumed to be suddenly imposed over the top surface of a laminated plate by, for example, a laser heating. As the temperature is raised, the plate is bent by the through the thickness temperature gradients. The temperature distribution at an arbitrary time t after the initiation of heating has already been known. Utilizing this result and modeling the portion of the plate consisting of the two circular plates above and below the disc-shaped crack as two lapped circular plates hinged at their rims, the deflection of the laminated plate is theoretically determined. It is found that the portion of the plate above the disc-shaped delami … More nation causes local buckling due to radial compressive stress induced by the temperature gradients. It is shown that this buckling would greatly promote the growth of delamination, since the energy release rates become very large.Second, we consider the growth of a disc-shaped interface crack by the low velocity impact. The impact is assumed to be made by the strike of a freely falling rigid column with large mass at the point of the plate surface directly above the center of the disc-shaped crack. Based on the characteristic function expansion methods, the concentrated force applied at the point of collision and the deflection of the plate are theoretically determined as functions of the time t after the instant of impact. By comparing the results with experiments, the present analyses are well confirmed. The energy release rate is also derived as a function of time t. It is shown that the energy release rate becomes about three times larger than that for the case of statically applied load. Less

考虑包含内部盘形界面裂纹的层合板，本研究的主要目的是推导能量释放率，这是决定界面裂纹扩展条件的最重要参数。首先，我们考虑这种情况。当层压板受到热冲击时，假设通过例如激光加热在层压板的顶表面上突然施加恒定的热通量，当温度升高时，板被贯穿弯曲。厚度温度梯度。加热开始后的任意时间 t 已经已知，利用该结果并将由盘形裂纹上方和下方的两个圆形板组成的板部分建模为在其边缘处铰接的两个搭接圆形板，挠度。从理论上确定了层合板的盘形分层上方的部分由于温度梯度引起的径向压应力而导致局部屈曲。分层的增长，因为能量释放率变得非常大。其次，我们考虑低速冲击引起的盘形界面裂纹的增长，假设冲击是由大自由落体刚性柱的撞击造成的。基于特征函数展开法，理论上将碰撞点上施加的集中力和板的挠度确定为时间的函数。 t 撞击瞬间后通过比较结果。通过实验，本分析也得到了作为时间 t 的函数的结果，表明能量释放率比静态施加负载的情况大约三倍。

项目成果

期刊论文数量（9）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Local Delamination Buckling of a Laminated Beam Due to Three-Point Bending

三点弯曲引起的叠层梁局部分层屈曲

DOI：
发表时间：
2006
期刊：
Transactions of the Japan Society of Mechanical Engineers(A) Vol. 72, No.722
影响因子：
0
作者：
K.Fukagawa;M.Oda;M.Aritomi;M.Toya
通讯作者：
M.Toya

Energy Release Rates for an Edge Delamination of a Laminated Beam Subjected to Thermal Gradient

热梯度作用下叠层梁边缘分层的能量释放率