中国激光, 2014, 41 (6): 0603003, 网络出版: 2014-04-09
激光冲击波诱导膜基系统动态应力应变
Dynamic Stress-Strain of Film-Substrate System Induced by Laser Shock Wave
激光技术 激光冲击波 膜基系统 残余应力 动态应变 laser technique laser shock wave film-substrate system residual stress dynamic strain
摘要
采用不同能量的脉冲激光多点单次冲击3种不同界面结合强度的膜基系统,利用X射线衍射(XRD)技术检测膜基系统残余应力,并用聚偏二氟乙烯(PVDF)传感器技术采集膜基系统的动态应变信号,建立了膜基系统激光冲击波加载模型,探索了激光离散划痕膜基系统的失效形式。结果表明,激光冲击后,2024铝合金表面以及膜基系统冲击光斑中心的残余应力都呈增大的趋势。膜基系统的动态响应与膜基界面结合强度及激光能量有关。激光离散划痕膜基系统的失效形式有两种:一是反射拉伸波导致薄膜剥落;二是膜基系统间的剪切应力导致薄膜剪切失效。
Abstract
The laser shocks of different pulse energies are used to perform a single impact on every multi-point of three kinds of the film-substrate system with different interface bonding strengths. The residual stress of target surface is detected by X-ray diffraction (XRD) technique, and the dynamic strain signal is collected by polyvinylidene fluoride (PVDF) sensor. Then a loading model of the laser shock wave on film-substrate system is established. Finally, the failure modes of film-substrate system based on laser discrete scratch are explored. The results show that the residual stress both on the surface of the 2024 aluminum alloy and the impact spot center of the film-substrate system increase after laser shock. The dynamic response of film-substrate system is related to the bond strength of film-substrate interface and the energy of laser. There are two failure modes of film-substrate system based on laser discrete scratch, one is the reflect stretch wave lead to membrane detached from the substrate, the other one is the shear stress of film-substrate system lead to film shear failure.
冯爱新, 钟国旗, 薛伟, 施芬, 庄绪华, 何叶, 陈风国. 激光冲击波诱导膜基系统动态应力应变[J]. 中国激光, 2014, 41(6): 0603003. Feng Aixin, Zhong Guoqi, Xue Wei, Shi Fen, Zhuang Xuhua, He Ye, Chen Fengguo. Dynamic Stress-Strain of Film-Substrate System Induced by Laser Shock Wave[J]. Chinese Journal of Lasers, 2014, 41(6): 0603003.